Exhibit 99.1

NI 43-101 Technical Report

Preliminary Economic Assessment for the Toroparu Project

Cuyuni-Mazaruni Region, Guyana

Prepared by:

Vaughn Duke, Pr.Eng.

Jan Eklund, P.E.

Pamela De Mark, P.Geo.

Prepared for:

Aris Mining Corporation

1021 West Hastings Street

Suite 2400

Vancouver BC V6E 0C3

Canada

Effective Date: October 21, 2025

Report Date: October 28, 2025

NI 43-101 Technical Report Preliminary economic assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana.

Forward looking information

This technical report may contain or incorporate by reference information that constitutes “forward-looking information” or “forward-looking statements” (collectively, forward-looking information) within the meaning of the applicable securities legislation. All statements, other than statements of historical fact, contained or incorporated by reference in this technical report including, but not limited to, statements related to those items listed below, constitute forward-looking information. Forward-looking information involves known and unknown risks, uncertainties, and other factors that may cause the actual results, performance or achievements of Aris Mining to be materially different from the forward-looking information contained herein. When used in this technical report, such information uses words such as “aims”, “anticipates”, “assumes”, “believes”, “budget”, “committed”, “continue”, “plans”, “project”, “endeavors”, “ensures”, “estimates”, “expects”, “focus”, “forecasts”, “forward”, “guidance”, “intends”, “likely”, “opportunity”, “outlook”, “pending”, “possible”, “potentially”, “predicts”, “proposed”, “scheduled”, “seeks”, “strives”, “targets” or variations of such words and phrases or statements that certain actions, events or results “can”, “could”, “generally”, “may”, “might”, “should”, “will” or “would” occur or be achieved and any other similar terminology.

The forward-looking information contained herein reflects current expectations regarding future events and operating performance and speaks only as of the date of this technical report. Generally, forward-looking information involves significant risks and uncertainties; therefore, it should not be read as a guarantee of future performance or results and will not necessarily be an accurate indication of whether or not such results will be achieved. Undue reliance should not be placed on such statements. A number of factors could cause the actual results to differ materially from the results discussed in the forward-looking information. Although the forward-looking information is based on what management of Aris Mining believes are reasonable assumptions, Aris Mining cannot assure readers that actual results will be consistent with the forward-looking information.

This technical report includes forward-looking information pertaining to, among other factors, the following: the projections, assumptions and estimates related to the Project, including, without limitation, those relating to development, capital and operating costs, production, grade, recoveries, metal prices, life of mine, mine sequencing, economic assumptions such as capital expenditures, cash flow and revenue, mine design, permitting and licensing, mining techniques and processes, timing of estimated production, equipment, staffing, emissions, use of land, estimates of mineral resources, use of energy storage technologies, the timing and expectations for other future studies, the operation of Aris Mining, the development and future operation of the Project, and the ability to secure permits for the Project.

Forward-looking information is based upon a number of estimates and assumptions that, while considered reasonable by Aris Mining as of the date of such statements, are inherently subject to significant business, economic and competitive uncertainties and contingencies. With respect to forward-looking information contained herein, the assumptions made by Aris Mining include but are not limited to:

Forward-looking information is based on current expectations, estimates and projections that involve a number of risks which could cause the actual results to vary and, in some instances, to differ materially from those described in the forward-looking information contained in this technical report. These material risks include, but are not limited to:

NI 43-101 Technical Report Preliminary economic assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana.

Readers are cautioned that the foregoing lists of factors are not exhaustive. There can be no assurance that forward-looking information will prove to be accurate. Forward-looking information is provided for the purpose of providing information about management’s expectations and plans relating to the future. The forward-looking information included in this technical report is qualified by these cautionary statements and those made in Aris Mining’s other filings with the securities regulators of Canada including, but not limited to, the cautionary statements made in the “Risks and Uncertainties” section of Aris Mining’s Management’s Discussion and Analysis for the three and six months ended June 30, 2025 which is available on Aris Mining’s website at www.aris-mining.com, on SEDAR+ at www.sedarplus.ca and on Aris Mining’s profile with the SEC at www.sec.gov.

NI 43-101 Technical Report Preliminary economic assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana.

The forward-looking information contained herein is made as of the date of this technical report and Aris Mining assumes no obligations to update or revise it to reflect new events or circumstances, other than as required by applicable securities laws.

Non-GAAP financial measures

This technical report refers to a number of non-GAAP financial measures, which are not measures recognized under International Financial Reporting Standards (IFRS) and do not have a standardized meaning prescribed by IFRS. These non-GAAP financial measures described below do not have standardized meanings under IFRS, may differ from those used by other issuers, and may not be comparable to similar financial measures reported by other issuers. Accordingly, these measures are intended to provide additional information and should not be considered in isolation or as a substitute for measures of performance prepared in accordance with IFRS.

Cash costs – Cash cost and cash cost per ounce ($ per oz) are a common financial performance measure and ratio in the mining industry; however, they have no standard meaning under IFRS. Cash cost ($ per oz) is calculated by dividing total cash costs by the number of gold ounces projected to be produced on a payable basis.

All-in sustaining costs (AISC) – AISC and AISC ($ per oz) sold are a common financial performance measure and ratio in the mining industry; however, they have no standard meaning under IFRS. AISC is calculated by dividing AISC by the number of gold ounces projected to be produced on a payable basis.

Earnings before interest, taxes, depreciation and amortization (EBITDA) – EBITDA is a common financial performance measure in the mining industry; however, it has no standard meaning under IFRS. EBITDA represents earnings before interest, income taxes and depreciation, depletion and amortization.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Contents

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

This technical report has been prepared for Aris Mining Corporation (Aris Mining) in compliance with the disclosure requirements of National Instrument 43-101 – Standards of Disclosure for Mineral Projects (NI 43-101) to disclose material updates to the Toroparu Project (Toroparu, the Project, or the Property) resulting from updated mineral resource estimates and the results of a preliminary economic assessment (PEA).

The Project contains two gold deposits with mineral resources, referred to as the Toroparu deposit and the Sona Hill deposit (collectively Toroparu unless otherwise indicated). The Sona Hill deposit is located approximately 5 km to the southeast of the Toroparu deposit. The Project and adjacent properties are collectively known as the Upper Puruni Concessions. Toroparu is an undeveloped, PEA stage open pit gold project.

This PEA outlines a long life open pit gold mine with robust economics and low operating costs. The Project will generate significant long term benefits for Guyana.

The Toroparu and Sona Hill deposits have been defined by nearly 800 drillholes. The mineralization at the main Toroparu pit has been defined over a strike length of 1.3 km, 500 m across strike, down to a depth of approximately 550 m below surface. Two smaller pits are located to the northwest and southeast of the main Toroparu pit. Sona Hill has been defined over a strike length of 950 m, 300 m across strike, down to a depth of around 200 m below surface.

A conventional open pit mining operation has been designed to mine mill feed from three pits at Toroparu and one pit at Sona Hill at a rate of 7 million tonnes per annum (Mtpa) utilizing an owner operated mining fleet.

The processing plant has been designed to separately treat surface oxidized material and underlying sulphide mill feed types on a campaign basis at a rate of 7 Mtpa using industry standard gravity concentration, carbon in leach, and flotation methods. The gravity concentrator will produce a gold and silver doré from oxide material and gold, silver, and copper doré from sulphide material. The carbon in leach circuit will produce a gold and silver doré from both oxide and sulphide material. The flotation circuit will produce a gold and silver rich copper concentrate from sulphide material at Toroparu only as Sona Hill has a low copper content. The oxide processing circuit enables stable operating conditions with predictable reagent use and minimal logistical overhead and provides a low cost, high recovery gold profile for early stage production. The operating cost for the sulphide processing operation is primarily driven by additional power and reagent requirements and high concentrate handling costs, but results in greater overall revenue at moderate incremental cost. The sulphide circuit is competitive with solid metallurgical recoveries and commercially marketable concentrate quality. Both processing routes deliver positive operating margins, confirming the economic robustness of the Project under the current design and energy assumptions. The results reinforce the scalability of the processing plant.

There is readily available water within the Project area for all aspects of the operation including mining, processing, the camp, and other activities. Water will be sourced from the Puruni River, which passes through the mining area, as well as from groundwater, rainwater, and water recycled from the processing plant and tailings management facility.

The peak workforce during Project construction is estimated at 1,763. During operations, the peak workforce is estimated at 744. The Project will target a high percentage of the workforce to be hired from within Guyana.

The Project’s expected mine life of 21.3 years is based on measured, indicated, and inferred material in the current mineral resource estimate, and there are opportunities for future mine extension if additional mineral resources are defined through continued exploration. The production profile is supported by a consistent milled grade ranging from 1.0 to 1.3 grams per tonne (g/t) gold. The long, steady production profile highlights the grade continuity of the deposit. In addition, the optimized pits and designs were constrained using a gold price assumption of $1,950 per ounce and a cut-off grade of 0.45 g/t Au. This conservative approach indicates meaningful upside potential for resource and mine-life expansion in a higher gold price environment.

Over its life, the Project is expected to produce doré and copper concentrates containing 5.0 million ounces (Moz) of gold, 4.9 Moz of silver, and 260 million pounds (Mlb) of copper. The average annual gold production is estimated at 235 thousand ounces (koz) over the mine life.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The total estimated upfront capital expenditure is $820.3 million, including pre-production costs and $96 million of contingency. This reflects a $38 million initial capital reduction compared to a mining fleet purchase scenario, as the $73 million cost of the initial mining fleet is reduced to approximately $35 million of upfront and construction period lease payments. The strategy is to maintain access to modern, well supported equipment under comprehensive maintenance and parts supply programs over the long +20 year mine life. In addition, the Project has a historic precious metals purchase agreement (PMPA) with Wheaton Precious Metals International Ltd (WPMI) for an additional $138 million of committed funding, further reducing upfront funding requirements to $682 million.

The original PMPA was entered into in 2013 and amended in 2015, when the Project was owned by Sandspring Resources Ltd. (Sandspring), a single-asset junior developer. Under this agreement, WPMI may elect to provide $138 million in construction funding following completion of a full development plan, in exchange for the right to purchase 10% of the Project’s gold production and 50% of its silver production at fixed prices of $400 per ounce of gold and $3.90 per ounce of silver, with both prices subject to escalation beginning on the fourth anniversary of commercial production. The parties intend to explore opportunities for amending the terms of the agreement to align with the updated Project parameters.

Plant throughput is expected to ramp up quickly following mechanical completion and commissioning, supported by a large stockpile of pre-strip and pre-production mill feed accumulated during the construction period. By the end of the three year construction phase, approximately 6.1 million tonnes of mineralized material are expected to be stockpiled adjacent to the process plant. This stockpile represents the majority of the first year’s mill feed and provides operational flexibility during the start up period.

The pre-production stockpile enables a low risk transition into operations, ensuring consistent mill feed as mining advances and allowing for controlled optimization of the crushing and processing circuits and confirmation of metallurgical recoveries of near surface mill feed.

With this strategy, plant throughput is forecast to reach nameplate capacity of 7.0 Mtpa within the first operating year, maintaining steady state production thereafter. The approach minimizes start up risk, smooths working capital requirements, and enhances the reliability of early year cashflow projections presented in the economic analysis.

The cumulative after tax net cash flow is estimated at $3.9 billion, including all initial capital costs, PMPA financing, pre-production costs, sustaining capital costs, closure costs, and contingency. At the base case assumption of $3,000 per ounce of gold, the life of mine average cash costs per ounce of gold are estimated at $826 and all in sustaining costs (AISC) per ounce of gold are estimated at $1,289. The project has an after tax net present value at a 5% discount rate (NPV5%) of $1.8 billion, an internal rate of return (IRR) of 25.2%, and a pay back period of 3.0 years.

The Project is estimated to contribute $2.2 billion in income taxes and $1.2 billion in royalty payments to the Guyanese government.

The sensitivity analysis shows that at higher gold prices, returns increase substantially beyond the attractive levels of the base case scenario, as shown in Table 1-1.

All dollar amounts presented in this technical report are expressed in U.S. dollars, unless otherwise indicated.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The Project is located in the Cuyuni-Mazaruni Region of Guyana, approximately 215 kilometres (km) southwest of the capital city of Georgetown.

Road access to the Property from Georgetown is via 110 km of paved highway south to the town of Linden, then 18 km of public gravel road to Bartica, a ferry crossing of the Essequibo River at Bartica to Itaballi, then 200 km of public gravel road to the south gate at Toroparu Junction, then 25 km north to the Project site. Overland travel time is approximately 10 to 12 hours in the dry season.

The Project can also be accessed via a one hour, 220 km charter flight from Eugene Correia International (Ogle) Airport in Georgetown to the 650 m long unpaved airstrip at the Project, which can accommodate Cessna Caravan flights holding up to 13 persons or 1,200 kg of cargo. The airstrip is licensed and certified by the Guyana Aviation Agency.

Heavy equipment and cargo may be transported by small ocean-going vessels and barges on the Essequibo River to Itaballi, then loaded on to trucks for the 230 km overland journey to Toroparu, crossing the Puruni River at the town of Puruni Landing, located approximately 60 km from Itaballi, on a company operated 40 tonne ferry barge.

The Project is 100% owned by Aris Mining through its indirect, wholly owned subsidiary, ETK, Inc. (ETK).

A summary of the Upper Puruni Concessions is provided in Table 1-1. Mineral properties in Guyana allow for four scales of operation. ETK holds or has applied for each of the four types of titles, including Mining Permits (MPs), Prospecting Permits Medium Scale (PPMSs), and Small Scale Claims, and two open Prospecting Licenses (PLs) applications which have been with the Guyana Geology and Mines Commission (GGMC) for approval since February 2020. Rentals on the claims and permits controlled by ETK are payable annually by the expiry date of each claim and permit. A work performance bond equal to 10% of the approved budget is required for mining licenses.

The four scales are defined as follows:

ETK is the beneficial holder of all right, title and interest in the lands subject to the Project and therefore also has all surface rights.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The Toroparu deposit is located on property that was originally subject to the Mining Joint Venture Agreement (as defined herein) dated effective August 1, 1999, and as amended and restated in 2008 by the A&R Joint Venture Agreement (as defined herein).

In March 2020, ETK exercised its option under the A&R Joint Venture Agreement to purchase all of Mr. Alfro Alphonso’s right, title and interest to the claims and permits on the Property listed in Appendix A hereto and all minerals and mineral deposits, ores, concentrates, metals, materials, tailings, dumps and mine wastes, in, on and under the claims (the Option Interest) excepting and reserving only to Mr. Alphonso the right to conduct the alluvial mining activities on certain lands not associated with the Project, all as more particularly described in the A&R Joint Venture Agreement, and the use by Mr. Alphonso of certain roads and an airstrip constructed by ETK. ETK paid $20 million to exercise the option to acquire the Option Interest and extinguish its obligations to make further payments under the A&R.

In connection with the option exercise, Mr. Alphonso delivered to ETK a written affirmation, declaration of trust and receipt acknowledging that he hold all lands and permits subject to the A&R Joint Venture Agreement in trust for the exclusive benefit of ETK until such time that the GGMC (as defined herein) and the Minister of Natural Resources of Guyana convert certain of the Small Scale Claim licenses and Mining Permits that are subject to the A&R Joint Venture Agreement to large scale Mining Licenses, and issue the same in the name of ETK. Mr. Alphonso further acknowledged that he is obligated to take any such action as may be reasonably requested by ETK, the GGMC or the Minister of Natural Resources to complete such conversion.

The Sona Hill deposit is located on property that was originally subject to the Godette Joint Venture (as defined herein) effective April 1, 2008. The Godette Heirs remain the registered owners of four mining permits but have irrevocably contributed and committed all their right, title, and interest in the mining permits for the benefit of ETK and the Godette Joint Venture and have granted ETK the exclusive right to conduct operations until such time as the large scale mining licenses have been secured. The cost of such conversion process is the responsibility of ETK but the Godette Heirs have agreed to execute such documents and agreements and take such actions as are reasonably necessary to assist in the transition of the mining permits to large scale mining licenses.

The Toroparu PMPA refers to the Amended and Restated Precious Metals Purchase Agreement among WPMI, Aris Mining Toroparu Holdings Ltd. (formerly GoldHeart Investment Holdings Ltd. (GoldHeart)), a wholly-owned subsidiary of Aris Mining, and Aris Mining Guyana Holdings Corp. (formerly Sandspring, an indirect, wholly-owned subsidiary of Aris Mining) dated April 22, 2015.

Pursuant to the terms and conditions of the Toroparu PMPA, WPMI has agreed to purchase 10% of the gold and 50% of the silver production from the Project in exchange for cash deposits totalling $153.5 million. WPMI has made initial payments totalling $15.5 million, with the remaining $138.0 million to be paid in instalments during construction of the Project, subject to WPMI’s election to proceed following receipt of a final feasibility study for the Project, environmental study and impact assessment and other project related documents.

A consulting agreement was executed between ETK and Alphonso & Sons (A&S) on November 1,2013 (the Consulting Agreement) and which survived the exercise by ETK of the option under the A&R Joint Venture Agreement as described above. Pursuant to the consulting agreement, A&S is to be paid, commencing on the first anniversary of ETK receiving cashflow sufficient to develop and construct a conventional open pit mining and flotation and cyanide leach process operation on the Property with on-site and off-site support operations (with such cash flow to be determined in a definitive feasibility study), eight annual payments of a minimum of $1.0 million adjusted upwards in accordance with the indexing formula set out in the Consulting Agreement (to a maximum of $2.0 million), followed by five extended payments of a maximum of $1.0 million (provided the daily price of gold averaged over a twelve-month period or a calendar month period, as applicable, exceeds $1,750 per ounce) subject to downward indexation based on a formula set out in the Consulting Agreement. Under the base case gold price of $3,000 per ounce applied in this study, the aggregate amount payable to the consultant under the Consulting Agreement is estimated at $21 million and has been considered in the financial analysis.

ETK executed a mineral agreement with the Government of Guyana on November 9, 2011 (the Mineral Agreement) that details all fiscal, property, import-export procedures, taxation provisions, and other related conditions for the continued

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

exploration and future mine development and operation of an open pit mine at Toroparu. The Mineral Agreement implements a two-tiered gold royalty structure of 5% of gold sales at gold prices up to $1,000 per ounce and 8% of gold sales at gold prices above $1,000 per ounce, as well as a royalty of 1.5% on sales of other valuable metals and minerals.

To the extent known, there are no other royalties, back-in rights, payments, or other agreements and or encumbrances to which the Property is subject.

Aris Mining is not aware of any significant factors or risks that may affect access, title, or the right or ability to perform on-going work programs on the Property.

The first known gold mining in the Project area was by alluvial mining methods around 1887. Regional and local mapping was undertaken in 1950. In 1997 Mr. Alphonso began mining old tailings and river alluvium at Toroparu and by 1999 the alluvial material was mostly exhausted and work proceeded deeper into the underlying saprolite, which eventually developed into the Toroparu saprolite open pit. This operation continued until 2001.

Exploration by ETK at Toroparu began in 1999 with the Alphonso Joint Venture, which named ETK as the Project operator. Between 1999 and 2018, ETK conducted extensive auger drill sampling campaigns, geochemical and trench sampling, and geophysical surveys around the Toroparu saprolite open pit and on a regional scale. ETK conducted intermittent, seasonal test mining from saprolite at the saprolite open pit from late 2004 to early 2007. The first diamond drilling on the Property began in late 2006 and the first mineral resource estimate was prepared in 2008. In 2009, ETK conducted an initial metallurgical scoping test program on core samples from the Toroparu deposit.

On November 24, 2009, Sandspring acquired 100% of GoldHeart, which through its wholly owned subsidiary ETK held the mineral and prospecting rights to the Project and adjacent properties.

Sandspring began a diamond drilling program in 2010, conducted geophysical surveys over the Toroparu deposit and reconnaissance grids over other prospects, and completed two mineral resource estimates in 2010. In 2011, Sandspring conducted a mineral resource definition diamond drilling campaign that identified the main lithologies and controls on mineralization. Additional diamond drilling was conducted later in 2011 to explore for nearby satellite deposits. In 2011, Sandspring prepared an updated mineral resource estimate and PEA and a prefeasibility study (PFS) level pit slope design report. Other exploration work conducted by Sandspring in 2011 included a regional saprolite geochemistry sampling program, semi-regional and detailed geochemical sampling, geophysical surveys, and a light detection and ranging (LIDAR) survey. In 2012, Sandspring completed diamond drilling programs and prepared an updated mineral resource estimate and PEA. Other exploration work in 2012 included regional and detailed auger sampling, geochemical sampling surveys, and reverse circulation drilling. In 2013, Sandspring completed a mineral resource estimate and the first mineral reserve estimate for an open pit project as part of a PFS (the 2013 PFS).

On November 11, 2013, Sandspring completed a $148.5 million precious metals streaming agreement with Silver Wheaton (now WMPI), with the capital commitment representing approximately 30% of the $464 million project finance required for the Toroparu Project as determined in the 2013 PFS. The precious metals streaming agreement was subsequently amended in 2015.

Following the 2013 PFS, Sandspring continued to conduct exploration to evaluate other areas on the Property, including auger and soil sampling of regional targets and exploration diamond drilling. Diamond drillhole programs were conducted at Sona Hill in 2015, 2016, and 2018, and utilized for the first mineral resource estimate for Sona Hill in 2018. Other work at Sona Hill included geochemical sampling and geophysical surveys conducted between 2015 and 2016. Additional diamond drillholes were completed at other exploration targets in 2016 and 2018. Sandspring changed its name to Gold X Mining Corp. (Gold X) on November 29, 2019. Diamond drilling programs were undertaken in 2020 and 2021.

On June 4, 2021, Gran Colombia Mining Corp. (Gran Colombia) acquired all of the issued and outstanding shares of Gold X, and indirectly, the Project. On November 29, 2021 Gran Colombia changed its name to GCM Mining Corp (GCM Mining). GCM Mining completed an updated mineral resource estimate and PEA on the Project in 2021. GCM Mining also began pre-construction activities in 2021, undertook infill drilling, and worked with the local governmental agencies to finalize the

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

amended mining license for a large-scale mining license incorporating an open pit and underground mine operating plan as outlined in the 2021 PEA.

On September 26, 2022, Aris Gold Corporation completed a business combination with GCM Mining, and the combined entity was renamed Aris Mining. Following the business combination, Aris Mining started a re-evaluation and optimization process for the Project, reduced the previously planned construction expenditures, and undertook a new detailed structural analysis and in early 2023 prepared an updated geological model and mineral resource estimate.

None of these historical estimates and studies are considered to be current. They should not be relied on and have been superseded by the current mineral resource estimate and PEA disclosed in this technical report.

Regionally, the Toroparu and Sona Hill deposits are located in the Amazonian Craton of the Guiana Shield, within the northwest trending Puruni volcano-sedimentary belt, in a sequence of meta-sedimentary and meta-volcanic rocks located along the contact of a small intra-belt pluton. Other gold deposits in Guyana related to similar intrusive bodies include Aurora, located approximately 50 km to the northeast of Toroparu, Oko and Oko West, located approximately 140 km to the east of Toroparu, and Omai, located approximately 180 km to the southeast of Toroparu.

Locally, the Toroparu and Sona Hill deposits are hosted in a sequence of meta-sedimentary and meta-volcanic rocks in a greenstone belt between Proterozoic aged granitoid batholiths.

At the Property, thin, discontinuous mineralized shear zones at the Toroparu deposit are developed mainly in volcanic rocks. Higher grade, discontinuous shear zone hosted mineralization is narrow and mostly parallel to the schistosity. The main controls on mineralization are the west-northwest striking axial planar schistosity and vein swarms that are well developed in the volcanic rocks, and the folded contact between an intrusive complex and the volcanic rocks, particularly the contact of an igneous breccia that forms an important rheological contrast, similar to many other orogenic gold deposits that are strongly controlled by competency contrasts. The Toroparu deposit dips roughly 55° to the west. The Sona Hill deposit has similar controls on mineralization but strikes to the north and dips around 30° to the west.

Two dyke phases are present including hornblende porphyritic andesite dykes and dolerite dykes. Most dykes have an apparent thickness of less than 0.5 m, but some dykes up to 2.5 m thick also occur. Despite being sheared and folded, the dykes are mostly non-mineralized, although some mineralized veins occur along the contacts. Some of these dykes are cut by mineralized shear zones. The dykes are less abundant and more discontinuous at Sona Hill compared to Toroparu.

A thick, gradational, 10 to 35 m thick layer of saprolite with preserved mineralized quartz veins and veinlets, showing evidence of some gold leaching, is present at the surface at Toroparu and reaches up to 60 m thick at Sona Hill. The overburden has abundant low grade gold mineralization but little high grade.

Mineralization at the Toroparu deposit estimated as mineral resources in the main zone has a volume of around 1.3 km along strike, around 500 m across strike, and a depth of 550 m. There is a zone of mineral resources approximately 1.1 km to the southeast of the main zone with a volume of around 400 m along strike, 230 m across strike, and a depth of 250 m. There are a few other small zones of mineral resources on the order of 100 m long along strike of and parallel to the main zone. The mineralized shear zones are narrow and discontinuous. Sona Hill has a volume of around 950 m along strike, up to 300 m wide, and a depth of around 200 m. Sona Hill is characterized by a lower copper content. Both deposits are open at depth.

The main body of mineralization at Toroparu is characterized by three different vein assemblages including:

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The interpretation of the deposit type at Toroparu is uncertain, with possibilities including an unusually copper rich orogenic gold deposit on the basis of the host greenschist metamorphic rocks and a strong control of mineralization due to competency contrasts, as well as a metamorphosed porphyry gold-copper deposit. Recent structural interpretation work suggests that Toroparu is not a classic lode type orogenic gold deposit and is unlikely to be a deformed porphyry deposit (Pratt and Smeraglia, 2022). A disseminated or sheeted vein type deposit can be used as a guide for exploration planning purposes.

Exploration at the Property followed a typical progression from mapping, surface sampling and geophysical surveys to generate drilling targets, short auger drilling of the targets, and mineral resource drilling by reverse circulation and diamond drilling.

Regional and local mapping has been undertaken in phases since 1950, both by the title holders and by external parties, including the GGMC. The GGMC undertook regional mapping supported by geochemical drainage sampling in 2000, which showed gold and copper anomalies in the immediate Toroparu area.

ETK began auger drill sampling in 1999 and further auger drilling was completed by ETK and Sandspring between 2001 and 2018. Trench channel samples were completed by ETK in 2005, 2006, and 2009. In 2006 and 2007, ETK conducted a high resolution tri-sensor magnetic and radiometric airborne survey around the Toroparu saprolite open pit area. This identified a magnetic low area just to the north of a large magnetic high area of unknown origin. The survey outlined a number of magnetic and radiometric anomalies in the areas adjacent to the Toroparu saprolite open pit.

In 2010 and 2011, Sandspring conducted gradient array induced polarization and magnetometer surveys over the Toroparu deposit area and other prospects. The induced polarization surveys showed anomalies corresponding to the Toroparu granodiorite pluton. Chargeability was low over areas of high gold-copper mineralization despite the presence of sulfides. At Sona Hill, Sandspring conducted an induced polarization survey in 2015 to 2016 over the saprolite geochemical sampling grid, which suggested an extension of the shear zone to the west, with the potential for additional mineralization in the hangingwall. The chargeability survey did not reveal any significant results due to the low sulfide content of the Sona Hill mineralization. Resistivity did not provide reliable information to differentiate lithology, due to the similar mineralogy of the intrusives and volcanics. In 2011 and 2012, Sandspring conducted a regional saprolite geochemistry sampling campaign in the Upper Puruni area. Semi-regional and detailed geochemical sampling was performed on areas where alluvial mining activities showed gold potential. At Sona Hill, Sandspring conducted geochemical sampling and geophysical surveys during 2015 and 2016. In 2011, Sandspring flew a LIDAR survey over the Toroparu deposit to produce a detailed topographic contour map.

Drilling has taken place at the Property from 2006 to 2022, mostly for resource definition at the Toroparu and Sona Hill deposits, and for exploration at other prospects. All drilling at the Project has been undertaken on behalf of the Property owners by Orbit Garant Drilling Services (Orbit) of Canada. All diamond drilling was undertaken using a triple tube initiated as HQ diameter (77 mm) and completed through the first 30 to 40 m of saprolite into hard rock, and then reduced to NQ diameter (60 mm) for the remainder of the drillhole. There are no details available regarding the reverse circulation drilling

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

procedure. However, these holes are mostly located in non-mineralized or very low grade zones and have minimal impact on the mineral resource estimates.

A total of 1,326 drillholes for 265,948 m are present in the Project drilling database. The drillholes in the Toroparu and Sona Hill deposits have adequate spacing between holes to define mineral resources for the mineralization style. Some of the drillholes at the periphery of the deposits or with a wider drilling grid have not been considered for the mineral resources estimate. Drilling considered for the mineral resource estimate corresponds to 617 diamond drill holes at Toroparu and 152 diamond and 29 reverse circulation holes at Sona Hill. Both deposits are open at depth.

As the drillhole intersections through the mineralized zones are used as an input into the mineral resource estimate, the relevancy of the raw drillhole sample assay results are superseded by the mineral resource estimate and are more meaningfully described in the context of the mineral resource estimate.

The sample intervals were marked by the geologist and the core was cut in half with a diamond bladed saw. Saprolite samples were split with a trowel. Both the diamond bladed saw and trowel were cleaned before each sample. The majority of sample lengths are 1.5 m, with a minimum width of 0.5 m respecting lithological contacts. There are unmineralized narrow dykes less than 0.5 m, and in this case the sample was proportionally completed with wall rock up to 0.50 m.

The sampled half of the core was placed in a labelled bag with a tag number, and the remaining half of the core was retained as reference core kept in the core boxes and photographed.

All on-site sampling was conducted by company employees who managed the security and chain of custody throughout the receipt of the core at the drill rig, the logging, sampling, and delivery to the laboratory.

Sandspring initiated a QAQC protocol in 2010 for Toroparu and Sona Hill that included the submission of one coarse duplicate, two certified standards, and a blank sample for each 32 regular samples. Monthly QAQC reports of assay results were subject to a pass/fail process where QAQC data were evaluated against set parameters and were either passed or failed. Where the QAQC sample failed the evaluation, a corrective action was taken which sometimes included re-assay of the entire batch. Re-assays were subject to the same evaluation process.

QAQC data submitted with the Toroparu deposit drill samples prior to 2020 included 4,220 submissions from a pool of 14 different gold/copper certified standards, 2,784 coarse blanks, and 1,252 core duplicates. Ninety-two sample swaps or laboratory failures were identified in the results returned for the certified standards. The blank results returned indicate possible short-term calibration issues at the laboratory, but no significant grade contamination is evident. No issues are identified with the duplicate sample results.

During the 2020 to 2021 drilling campaigns at the Toroparu deposit, QAQC data submissions included 622 samples from a pool of five different gold/copper/silver certified standards and 854 coarse blanks. No issues were identified with the standard results, and no significant grade contamination is evident.

Drill samples from the Sona Hill deposit submitted during 2012 and 2017 to 2018 included 421 submissions from a pool of six different certified standards, 216 coarse blanks, and 257 core duplicate samples. No issues were identified with the standards, blank samples, and the duplicate samples.

Between June 1, 2011, to 2014, sample preparation was completed at the on-site facility managed and operated directly by Acme. The prepared samples were then flown to Acme Laboratories in Georgetown, Guyana, and from there shipped to either Acme of Santiago, Chile, or Acme of Vancouver, Canada, for analysis.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Before Acme was acquired by Bureau Veritas, it was accredited under the general ISO 9001:2000. Most of the sample were prepared on-site by Acme and analyzed at their facility in Chile. Acme is ISO 9001:2008 and ISO/IEC 17025:2005 certified, and sample preparation and analyses were done at their facility in Canada.

The samples sent to the MSA Laboratory were prepared and analyzed at their Georgetown facility. MSA has ISO 45001:2018 and ISO 9001 certifications, and ISO 17025 accreditation.

There are no records of accreditation for ACT. All the samples analyzed by ACT underwent preparation and analysis at their Georgetown facility.

Acme, MSA and ACT operate as independent commercial certified laboratories both locally and internationally and have no relationship with the past or present Project operators.

Sample preparation at Acme involved initial weighing and drying each sample. The entire sample was then crushed to 80% passing -10 mesh and a 250 gram split was taken and pulverized to 85% passing -200 mesh.

At MSA, the entire sample was dried and crushed to 70% passing -10 mesh. A 250 gram sample split was taken for each sample and pulverized to 85% passing -200 mesh.

There are no records of the sample preparation method used at the ACT facility.

All samples were assayed for gold using by fire assay on a 50 gram charge with atomic absorption spectrometry (AAS) finish. Any sample with an assay greater than 10 g/t Au was re-analyzed using fire assay with gravimetric finish. Most of the Toroparu samples were assayed for copper while at Sona Hill, copper analysis was performed selectively, given the low copper content at the deposit. Samples were not regularly assayed for silver. For copper and silver, the samples were analyzed by four acid digest with AAS finish on a 0.5 gram charge.

The qualified person responsible for geology verified the geological data supporting the mineral resource estimate through the personal inspections and through collaboration with the Project team, including:

In the opinion of the qualified person, the data used for the purpose of estimating the mineral resources are sufficiently reliable.

Numerous metallurgical testwork programs starting in 2009 have been undertaken to characterize the feed grade mineralization of the Toroparu and Sona Hill deposits, including both oxidized saprolite and sulphide fresh rock, and the material’s response to comminution, gravity concentration, rougher and cleaner flotation, and cyanide leaching. The testwork utilized samples that were representative of the growing mineral resource as it was known at the time of the studies. These studies included processing method trade off studies as well as refinements of the selected operating parameters, as the properties and response of the samples under the testwork conditions were increasingly better understood.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

A mineralogical assessment showed that the sample was dominated by silicates and with chalcopyrite the predominant sulphide mineral.

Gold deportment studies at a P80 of 150 microns showed that the majority of the gold was present as native gold, indicating that gravity recovery should be considered in the process flowsheet. Other gold minerals included electrum, maldonite, petzite, and hessite.

Liberation studies showed that the liberation of copper minerals improves substantially at grinds finer than 150 microns. In contrast pyrite is widely distributed with significant liberation in the range of 80 to over 90% at all size fractions. Copper minerals and pyrite have negligible mutual association, so producing a marketable concentrate was expected to be possible.

Comminution test results on samples from the Toroparu pits showed that the feed material is in the moderate to hard category and within the abrasive range. Testwork on saprolite samples from Sona Hill showed the feed material to be very soft and not abrasive. Testwork on sulphide rock samples from Sona Hill showed the feed material to be moderately hard and mildly abrasive.

Processing saprolitic material will add viscosity considerations, and the softness will reduce the power demand in the milling circuit. High saprolite blends may allow elevated processing rates of hard material.

The testwork includes flotation testwork, gravity recovery, cyanidation, flowsheet testing, the response of recovery to grind size, reagent consumption and optimization, detoxification.

The flotation, cyanidation, and gravity recovery testwork shows that the Toroparu and Sona Hill mill feed responds well to flotation and gravity recovery.

The combined metallurgical recoveries for sulphide material are estimated at 93% for gold, 78% for silver, and 88% for copper. For oxide material the combined metallurgical recoveries are estimated at 97% for gold and 46% for silver. Overall, recoveries are estimated at 93.6% for gold, 77.0% for silver, and 86.1% for copper.

There are no known processing factors or deleterious elements that could have a significant effect on the economic extraction of the mill feed that have not been considered and accounted for in the processing plan and economic model. Mineral analysis on the copper concentrates produced from the Toroparu deposit identified deleterious elements that may have some penalty on concentrates, including bismuth, selenium, tellurium, and arsenic.

The mineral resource estimate for open pit resources has been tabulated using a cut-off grade of 0.45 g/t gold, based on a gold price of $1,950 per ounce, an overall gold metallurgical recovery of 95%, a mining cost of $3.20 per tonne, a processing and surface infrastructure cost of $14.70 per tonne, a general and administration (G&A) cost of $4.60 per tonne, and an 8% gold royalty. The mineral resource estimate for underground resources has been tabulated using a cut-off grade of 1.5 g/t gold, based on the same assumptions as open pit resources with the exception of mining costs of $60 per tonne and G&A costs of $5 per tonne.

The mineral resource estimate is constrained within optimized pit and optimized stopes created using a gold price of $1,950 per ounce and cut-off grades of 0.45 g/t gold for open pit mineral resources and 1.5 g/t gold for underground mineral resources.

The Toroparu mineral resource estimate effective October 21, 2025, is shown in Table 1-2.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The Toroparu and Sona Hill deposits will be mined using conventional open pit mining methods. The operation will utilize conventional drill rigs, excavators, haul trucks, dozers, graders, water trucks, and utility vehicles.

Run of mine material from the Toroparu pits will be hauled from the pit benches to a dedicated run of mine stockpile located close to the Toroparu open pit area and processing plant. Run of mine material from the Sona Hill pit will be hauled approximately 8 km to the run of mine stockpile at the processing plant. Waste material will be hauled from the Toroparu and Sona Hill pits to their designated waste storage facilities located in close proximity around the two open pit areas. Topsoil will be stored separately for future rehabilitation requirements.

Material will typically be blasted in benches ranging from 10 to 20 m high, with 10 m benches assumed for the smaller equipment mining overburden and most saprolite, and 20 m benches for the larger equipment mining transition, sulphide rock, and selected areas of saprolite. Given the softness of the overburden and near surface oxidized saprolite, free digging and ripping opportunities will be considered where possible. Most of the overburden and approximately 75% of the saprolite is expected to be excavated without blasting.

The general mining related layout includes the Toroparu main, northwest, and southeast pits, the Sona Hill pit, a waste rock storage facility located to the northeast of the Toroparu pits, a waste rock storage facility located to the east of the Sona Hill pit, a low grade stockpile located to the west of the Toroparu northwest pit, a run of mine stockpile located at the processing plant, and haul roads.

Key considerations for the strategic mine plan and schedule included a 7.0 Mtpa mining and processing rate over a 21.3 year

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

mine life. Mining will be prioritized at the Toroparu main pit while production at the Toroparu northwest, Toroparu southeast, and Sona Hill pits will be delayed as long as possible to delay the required capital expenditures. The Toroparu main pit is planned to be mined in four phases to optimize access to higher gold grades, while the Toroparu northwest, Toroparu southeast, and Sona Hill pits are all planned to be mined in a single phase.

There is a three year construction period during which mill feed will be stockpiled for processing in year one. Production reaches 7.0 Mtpa in Year 2 and continues until year 21. The final 2 Mt of mill feed are mined in year 22.

The life of mine production is shown in Table 1-4.

The process plant design criteria and flowsheet are based on extensive metallurgical testwork as described in Section 13, and are based on an industry standard practice metallurgical flowsheet to treat two primary gold bearing rock types, including the oxidized saprolite and other near surface oxidized material and deeper sulphide rock, to produce two doré products and a copper-gold flotation concentrate. The two oxide and sulphide mill feed types will be stockpiled and processed separately during designated campaigns.

The process plant is designed to nominally treat 7.0 Mtpa of run of mine feed and will consist of crushing, grinding, an upfront gravity gold concentration circuit to produce doré, followed by a carbon in leach circuit to produce a second doré, and sulphide flotation for the sulphide feed type only to produce a copper-gold concentrate.

Cyanide contained in the tailings from the gravity concentrate and intensive cyanidation circuits will be neutralized by dosing with a hydrogen peroxide solution before recirculation to the milling circuit, ensuring a safe operating environment. Cyanide present in the carbon in leach tailings stream will be treated in an SO2/air cyanide destruction circuit to meet the environmental compliance requirements before being pumped to the tailings management facility.

The combined metallurgical recoveries for sulphide material are estimated at 93% for gold, 78% for silver, and 88% for copper. For oxide material the combined metallurgical recoveries are estimated at 97% for gold and 46% for silver. Overall, the operation is designed to recover 93.6% of the gold, 77.0% of the silver, and 88.4% of the copper contained in the total life of mine material.

There are no known processing factors or deleterious elements that could have a significant effect on the economic extraction of the mill feed that have not been considered and accounted for in the processing plan and economic model. Mineral analysis on the copper concentrates produced from the Toroparu deposit identified deleterious elements that may have some penalty on concentrates, including bismuth, selenium, tellurium, and arsenic. Further metallurgical testwork is required to better define the potential concentrate quality and therefore no penalties have been considered in the economic analysis.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The Project site infrastructure will be organized into primary areas including the Toroparu and Sona Hill open pits and processing plant with supporting services, the tailings management facilities, and the site-wide infrastructure including access roads, tailings pipeline, airstrip, and camp area.

The terrain presents challenges due to its low lying riverine areas and expansive flat regions between hills. Heavy rainfall periods increase the risk of inundation, requiring the open pits to be protected from flooding. Land reclamation strategies have been planned to optimize land use and enhance safety. These measures include diverting the rivers to protect the open pits from potential flooding and thereby ensuring operational stability and environmental safety.

Off-site infrastructure will also be required including access and logistical infrastructure located outside of the mining titles. The mine support facilities will comprise the typical components of an open pit mine, including an assay laboratory, core shacks, an independently operated vehicle fuelling facility, a secure explosive storage facility, lighting,

The process facilities will be supported by a primary terrace located on relatively level ground in close proximity to the Toroparu pits to minimize haulage distances and to minimize the required construction fill. The strategic placement offers enhanced access, security, and personnel movement and facilitates the easy supply of utilities such as the water and power to support both production operations and overall site efficiency. The process support facilities include the power plant and all required support infrastructure including stores, workshops, fuel station, medical services, and administration blocks. A helipad located close to the medical facility is also planned to facilitate the rapid medical evacuation of any injured personnel and can also double as emergency gold transport.

The current Project infrastructure includes a 200 person capacity camp, kitchen and mess hall, gym, security fencing and checkpoints, maintenance and welding workshops, carpentry shop, warehouse, water pump and water tank, freshwater pond, core sheds, drilling contractor’s facilities, the 650 m long airstrip, diesel generators and a 70,000 litre capacity fuel farm, and satellite internet. ETK also owns additional facilities along the Puruni road.

The tailings management facility is advantageously located relatively close to the processing plant within a natural valley, bounded by steep hills on the north, east, and west sides, requiring the construction of an embankment only along the southern perimeter, simplifying the engineering design and reducing both construction complexity and material requirements. The general topography slopes southward and the design takes advantage of this natural gradient with most of the drainage and conveyance infrastructure operating under gravity to direct flow to the southern side of the facility. The site is located outside of the one in one thousand year flood line and therefore mitigates the risk of flooding and ensures long term operational resilience.

The design aligns with the Global Industry Standard on Tailings Management, the Canadian Dam Association guidelines, and the requirements of the environmental permits.

The design was developed to a Class 5 level of accuracy as defined by the recommendations of the Association for the Advancement of Cost Engineering, which is considered appropriate for the PEA level study.

The design is inherently conservative and is based on maximum mining rates of 7.0 Mt per annum. The design is for a spigot deposition, downstream constructed, conventional thickened tailings management facility. The required capacity is 154 Mt over a 21.3 year mine life, but the design allows for a conservative total of 161.4 Mt over a 23 year period with a final embankment height of approximately 39 m.

The saprolite in the area of the planned facility basin, which averages approximately 10 m thick, has a low permeability and will serve as a natural barrier. It is envisaged that saprolite material will be used above the upstream face of the embankment to prevent seepage through the embankment, thereby protecting the structural integrity. The design also includes a comprehensive basin drainage system and stormwater management structures to effectively separate contact and non-contact water.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

A return water dam will be built to collect and store water released from the tailings facility, providing a controlled pond for recycling water back to the process plant. It will be located to the southeast of the tailings facility within a natural valley, bounded by hills on its eastern and western sides, with the general topography sloping southward. It will be lined with a 1.5 mm thick HDPE liner to prevent seepage and groundwater contamination.

A service road will provide operational access around both the facility and the return water dam.

The tailings facility embankment will be developed in three sequential stages to optimize construction cost. The initial stage provides for 17.6 Mt of capacity representing around 2.5 years of tailings storage with two subsequent raises to contain an additional 35.8 and 108 Mt. The construction period for the first stage will be 12 months, after which deposition will begin. The construction period of the second stage will be 18 months and the third stage will be 50.5 months. The downstream containment embankment and the return water dam embankments will be constructed using overburden rock sourced from the facility basin, selected rockfill, gravel, and crusher dust.

Tailings thickened to a solids content of 50% will be pumped from a central feed tank, located downstream of the thickener, to the facility via a slurry delivery pipeline. A ring main will be installed around the facility perimeter, and the tailings will be deposited into the facility through open ended spigots.

The water balance demonstrates that the proposed contact water management system, including the pool, return water dam, pump sump, and transfers, is sized to appropriately manage inflows within operating bands without exceeding the full supply level, provided the assumed treatment and pumping capacities are maintained.

A cut-off drain will be installed along the northern, eastern, and western perimeters of the site. Upstream groundwater collected in the cut-off drain will be conveyed and discharged into the clean water channels and outlet structures.

A network of drains will be installed throughout the tailings facility basin area. The drainage alignments follow the natural topography and meander within existing valleys. The drains will assist in controlling the phreatic zone within the tailings facility.

A floating pontoon system will pump supernatant water from the pool area into the return water dam. The tailings delivery system will operate in parallel with the return water system, in the opposite direction, with tailings conveyed from the processing plant to the tailings facility while the reclaimed supernatant water will be returned from the return water dam to the plant for make-up water. The return water dam levels will be optimized for storage and operational flexibility, and will be as empty as practically possible under normal conditions to provide sufficient surge capacity for accommodating a simulated one in 5,000 year storm event. On average, the return water dam will maintain a storage volume of approximately 20% of its total capacity to mitigate the risk of overflow.

Surface storm water management infrastructure will be designed, managed, and operated. Contact and non-contact water will be separated into dedicated water systems. Clean water diversion berms and channels will be installed along the tailings facility perimeter to accommodate the one in 100 year peak flow and safely divert non-contact run off to the natural watercourses. The contact water channels will lead to the sump and return water dam. A water treatment plant will treat excess water prior to being returned to the processing plant.

Standpipes will be installed initially in situ, in the embankment, and the formed beach to provide early monitoring of pore water pressures. Once the facility reaches a sufficient height, vibrating wire piezometers will be installed within the basin and embankments along monitoring lines to monitor phreatic surface activity and contribute to slope stability assessments. Continuous flow measurements will be conducted at all outlet drains to assess the effectiveness of phreatic zone drawdown within the facility. Flow meters will be installed on the decant system for continuous flow measurement. This ongoing monitoring will provide valuable data to evaluate overall facility performance against historical trends and facilitate proactive management of water pressures and slope stability.

Aris Mining will appoint an engineer of record to undertake quarterly and annual inspections and reporting of the dam status. ETK will submit all monthly monitoring data to the engineer of record for review and comment.

The tailings facility closure design will be aligned with recent, government approved projects in Guyana, and will include limited basin interventions and the construction of a spillway capable of conveying the regional maximum flood consisting of rock-lined channels terminating in a stilling basin at the downstream end. This basin will safely discharge flows.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Physical stability measures will be undertaken including final crest geometry and slope regrading to target long term factors of safety, buttressing or recontouring the embankment slopes if required. Water management will include surface water diversion channels around the facility to reduce inflows, a water treatment strategy for collected seepage, and a closure water balance. Monitoring and scheduled maintenance will be undertaken including the use of piezometers, inclinometers, survey monuments, seepage flow meters, and visual inspections of vegetation and erosion. Maintenance will include spillway clearing and drainage upkeep. Water quality monitoring of surface and groundwater will be undertaken to ensure compliance with the closure plan

The closure plan outlines closure objectives and design components to ensure long term physical and chemical stability, minimize seepage, protect downstream receptors, and support future sustainable land uses, aligned with regulatory and stakeholder commitments. The closure design criteria will be reassessed during the operation of the facility to improve geotechnical and hydrological criteria to ensure facility stability and to reduce the risk of failure over the extended closure period.

Two waste rock management facilities will be constructed for the Toroparu pits, including an 86.8 Mt capacity low grade mineralized waste rock management facility containing material between 0.30 to 0.45 g/t gold and a 591.4 Mt capacity waste rock management facility containing material less than 0.30 g/t of gold. The waste rock storage facility is located just to the northeast of the three Toroparu pits and the low grade storage facility is located to the west of the Toroparu northwest pit.

A single 41.7 Mt capacity facility will be constructed for the Sona Hill pit to contain all material that is less than 0.45 g/t of gold, located to the east of the open pit.

The facility locations were selected to minimize haulage distances and to accommodate infrastructure and surface water management. The facilities at the Toroparu pits also provide protection against extreme flood events.

The facilities were designed for long term stability and rehabilitation, with overall slopes of 21 to 23° to account for high rainfall conditions. Vertical expansion will be limited through controlled lift heights. The maximum height of the low grade facility is 68 m, 89 m at the Toroparu waste rock facility, and 70 m at the Sona Hill waste rock facility. The facilities have been designed to accommodate more material than is present in the current mine plan, at 20% additional capacity for the low grade facility, 9% for the Toroparu waste rock facility, and 5% for the Sona Hill waste rock facility.

The mine site has very low relief with shallow groundwater levels. The Project is drained by the Puruni and Wynamu rivers, the confluence of which was historically at the Toroparu southeast pit location, but has been altered by artisanal and small scale mining activities. The predominant flow direction is to the south-southeast over very flat surface topography. The rivers directly influence the proposed Project infrastructure, with all of the open pits located within the floodplain areas of the two rivers. The rivers will be diverted to allow for proper surface water management and to mitigate safety concerns associated with flood events by constructing stream diversion canals and levees. These rivers are the main receptors.

A water management strategy was developed to support the proposed open pit mining, incorporating the pit dewatering requirements and the necessary surface water diversion, water quality management, and infrastructure. Dewatering will be undertaken using in pit sumps to capture pit inflows into each pit and a series of pumps and piping. All water will be directed through a pipeline network placed close to the haulage roads to minimize interference with mining operations and to facilitate safe access for inspection and maintenance. The design includes flexibility to pump water to different destinations to cater for seasonal changes and water quality.

During commissioning, all plant water will be pumped at a rate of 561 litres per second from the Puruni River, and during operations the demand will drop to 53 litres per second. The water will be pumped to the process plant for use as reagent make-up, potable water, gland water, and process water.

The peak make up water demand for mining is 359,334 cubic metres per month and can be sourced from rainwater harvesting, abstracted from the Puruni and or the Wynamu rivers, as well as boreholes. Excess contact and mine water will be managed and treated if required before being discharged to the environment.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Offsite infrastructure includes the Project access road and the use of port access near Itaballi, from where all goods will be transported via road freight to the Project.

The primary access route to the Project begins at Camp 4 and extends to the Project site. This road is approximately 30 km long and in good condition, and will be upgraded to accommodate increased traffic. Road construction activities will be scheduled as part of routine road maintenance, utilizing waste rock material as it becomes available during construction. It is anticipated that the maintenance and widening process will be ongoing throughout the life of the mine.

From Camp 4, the main road continues to Georgetown via the Puruni Road. The section from Itaballi to Puruni has been largely rehabilitated with regular maintenance ongoing to ensure reliability. The remaining segment from Puruni to Toroparu, a distance of approximately 105 km, has been largely rehabilitated but heavy rainfall periodically affects the road’s drivability and requires ongoing maintenance.

The road will continue to be maintained during the mine’s operational life. Waste rock from the site can be used to reinforce weak zones and improve drainage, ensuring sustained access for the timely delivery of resources to the processing plant and to support ongoing operations. Alternatively, closer borrow pits should be identified in following studies to significantly reduce the cost of material transport.

Studies on offsite logistics for the transportation of concentrates from the Project were completed in 2013 and 2022. The proposed port facilities are located near Itaballi at a location on the south bank of the Cuyuni River, approximately 3.2 km upstream of the confluence with the Mazaruni River known as Pine Tree. The Pine Tree Landing port operation is planned to support the mine construction and operation, specifically for the transportation of equipment, materials, and supplies. The port will also function as a transhipment for import and export goods. Supplies will be delivered by barge from Georgetown Harbour to a newly constructed port/wharf at Pine Tree for storage and subsequent road transportation to the Project by truck. Trucks from the Project will return with copper concentrate to the Pine Tree Landing for storage and for both roll on, roll off and crane loading on barges destined for Georgetown.

The proposed port facility will include wharf loading and discharge areas, forklifts, reach stackers, cranes, logistics, truck maintenance, accommodation buildings, container and equipment laydown areas, third party fuel storage and fuelling facilities, and power generation and related utilities. The port facility will accommodate ocean going barges to transfer cargo between Georgetown and Pine Tree Landing via the Essequibo, Mazaruni, and Cuyuni rivers.

The potential exists to engage in strategic conversations with G Mining Ventures to share in capital and operating costs at their planned dedicated wharf and storage facility and associated barging systems serving their Oko West project.

There is no nearby power grid. The estimated power requirements for the planned process plant are approximately 50 MW, which will be supplied by a 50 MVA, 13.8 kV onsite heavy fuel oil power plant. The plant will consist of six generator sets rated at 9.28 MW, configured to provide an operational capacity of 46MW and an installed capacity of 55 MW, including one standby unit. The generating sets will comprise a four-stroke, V-type, 16 cylinder, turbocharged, and intercooled diesel engine capable of operating on heavy fuel oil, marine diesel oil, or light fuel oil.

The fuel system will manage the unloading, storage, treatment, and delivery of heavy fuel oil transported by road from Georgetown to the Project. Deliveries will be made using four daily 50,000 litre (50 cubic metre) capacity fuel tankers to sustain continuous operations at full load. The power plant’s average fuel consumption will be approximately 196 cubic metres per day. The site fuel storage system will consist of two main heavy fuel oil storage tanks, each with a 2,200 cubic metre capacity, providing approximately three weeks supply of full load operation.

Power will be distributed by overhead power line to the primary crushing area, tailings facility, as well as the open pit mine, accommodation area, and the main access gate.

The Project is located near the equator with year round high temperatures and humidity and seasonal tropical weather and climate. Site conditions are wet as a result of high humidity and bimodal annual rainfall ranging from 2,000 to 3,500 mm.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The topography is flat to gently undulating to hilly, with elevations ranging from 80 to 170 m above sea level at the Toroparu deposit and from 80 to 135 m above sea level at the Sona Hill deposit. In places there are hills with steep relief. The Project is located in an area of low seismic activity.

The majority of the Project is covered by secondary growth dense tropical forest and low lying swamps Four types of terrestrial ecosystems are represented at the Project, including mixed forests, liana forest, high hills, and low swamp forest. The area is considered to have a low species diversity relative to tropical rainforests with a total of 55 plant species comprised of 38 timber tree species and 17 plant species.

A total of 19 mammal species have been identified at the Project, the majority of which are fairly common in Guyana. A total of 52 fish species have been identified, none of which are endemic to Guyana, but several have economic and social values as important food sources. No endangered avifauna were identified. The jaguar, lesser seed finch, lowland tapir, red and green macaw, black headed parrot, and the blue headed parrot were identified and have a special classification by the Convention on International Trade in Endangered Species of Wild Fauna and Florida and the International Union for Conservation of Nature, however, there are known known locally rare, critically endangered, or endangered species at the Project.

The Project is located between the Mazaruni River and the Cuyuni River, about 40 km to the north, which are major tributaries of the Essequibo River that flows north to the Atlantic Ocean. In the immediate Project area, the main rivers are the Puruni River and the Wynamu River. The Puruni River flows southeast from its upper reaches near the Project site and the Wynamu River flows south to the confluence with the Puruni River, immediately south of the Project. The confluence of the two rivers has been disturbed by historical and present day artisanal mining which has blocked the natural course of the Wynamu River. Flooded areas occur in low lying areas of the Project site and where artisanal mining is present.

An ESIA was prepared in 2012 and an updated Environmental Management Plan (EMP) was prepared in 2021 as part of the Guyana Environmental Protection Agency (EPA) environmental permitting process for the Project.

Initial environmental baseline studies to support the development of the 2012 ESIA were conducted during wet and dry seasons in 2007, 2008, and 2010 that included characterization of the site and regional vegetation, wildlife, biodiversity, rare and threatened species, topsoil, geology, surface water, groundwater, water quality, groundwater pit inflows modelling, geochemical characterization studies, historic cultural properties, climate, air quality, odor, noise, and dust, and meteorological conditions.

Expanded environmental and social baseline studies were conducted in 2020 to 2021 to support an application for an environmental authorization variance. An updated biodiversity baseline survey was conducted during the wet season of mid 2022 and the dry season of late 2022 to record environmental conditions and seasonal variability. No critically endangered or endangered faunal species were recorded during the surveys.

The most significant environmental issue within the Project area relates to the disturbance caused by historic and on-going illegal artisanal and small scale mining activities. These activities have altered portions of the Wynamu and Puruni river channels and banks within the Project. Abandoned artisanal mining pits containing stagnant water have also created conditions conducive to the proliferation of malaria carrying mosquitoes. Baseline soil chemistry assessments completed in 2022 on historical artisanal tailings within the Project area identified elevated mercury concentrations.

The illegal artisanal and small scale miners gain access to the Project area either via unauthorized footpaths through the surrounding forests or through the Project’s main gate by misrepresenting themselves as members of groups holding legitimate mining claims adjacent to the Property. The Project works closely with the Guyana Environmental Protection Agency (EPA) and the GGMC to address illegal mining within the Project titles by regulating access, conducting regular security patrols, monitoring and documenting all unauthorized mining activities and associated environmental impacts, and submitting monthly reports to both the Guyana EPA and the GGMC. However, the Project does not have the legal authority to remove illegal artisanal miners or their equipment; this authority resides exclusively with the GGMC, the Guyana Police Force, and the Guyana EPA. Enforcement actions by these agencies occur intermittently and typically only provide a short term deterrence, as illegal miners often return to the area following the conclusion of such exercises.

To the extent known, there are no environmental liabilities to which the Property is subject.

The key permits necessary for Project construction and operation include an environmental permit and a mining license.

On October 15, 2024, ETK was granted a renewed environmental permit based on an application for permit renewal submitted on December 15, 2023. The renewed permit incorporates all Project activities, including the access road and Puruni Pontoon Crossing, and includes design, construction, operational, and monitoring and reporting compliance conditions. The renewed permit is valid for five years and will expire on September 30, 2029. Following the filing of this PEA, ETK will undertake the normal course notifications and consultations with the EPA before commencing construction, ensuring that the existing permit is updated to reflect the final Project plans.

ETK holds additional environmental permits for the Itaballi Landing Facility proposed fuel depot and wharf on the Mazaruni River and the Itaballi Laydown Support Facility at Aremu Junction. The permit was granted by the EPA on December 13, 2023, and expires on October 31, 2028.

All relevant Project environmental compliance thresholds and limits are specified in the 2012 ESIA, the 2021 updated environmental management plan, and the Project environmental permit, which were approved and granted in accordance with the Guyana Environmental Protection Act and Regulations, the Mining Act and Regulations, and other Guyana legislation and regulations relevant to the Project.

Where there are no applicable thresholds and/or limits specified in the Guyana regulations, the Project is mandated under the environmental permit to incorporate the IFC World Bank Group Environment, Health, and Safety Guidelines for Mining in the final design of all facilities and processes, as well as other applicable international best management practice.

A mining license is required to conduct commercial scale mining operations in Guyana. The application must include a technical and economic feasibility study, detailed mine and processing plans, an EIA, and an environmental management plan. A mining license is typically valid for 20 years, or for the life of the mine, whichever is shorter, and may be renewed at upon expiry if required. The license holder is required to pay an annual rental fee for each acre covered by the mining permit. An application for a mining license for the Project was first submitted in 2020 and resubmitted in 2022. The application remains under review by the Ministry of Natural Resources and the GGMC.

There are no formal or established communities or settlements within or in the immediate vicinity of the Project area and no established communities in proximity to the associated Project components, and accordingly there are no resettlement obligations. Mercury levels were not above detectable levels in soil, sediment, or water samples from the Project, which supports the interpretation that the areas has not been subject to extensive historical mining activity. No remnants of historical mining activity are present other than the existing former open pit mine. There are no known historical buildings, former settlement sites, or cultural heritage features within the Project area.

There are no villages or communities dependent on groundwater within the Project area, with the nearest village located at Puruni approximately 100 km away.

Development of the Project will provide a diversity of employment and socioeconomic opportunities to the country of Guyana. The Project will require skilled mine workers, services, material suppliers, contractors, and skills training. The direct income benefits of the Project will result in opportunities for indirect benefits such as support to local business, career opportunities for young adults, investment in non-mining related enterprises, and traditional agricultural, cultural, and artisan pursuits.

ETK currently employs 68 persons, including 65 Guyanese and three expatriates, with 13 based in Georgetown, 14 based in Itaballi, 3 based at the pontoon operation in Puruni, and 38 based at the Project camp. The employment numbers are approximately equal between basic and semi-skilled, skilled and professional, and supervisory roles, and 27% of the employees are female.

The peak workforce during Project construction is estimated at 1,763. During operations, the peak workforce is estimated at 744. The Project will target a high percentage of the workforce to be hired from within Guyana.

The capital cost estimate was prepared in accordance with the American Association of Cost Engineers Class 4 level, with an expected accuracy of -30% on the low side and +50% on the high side, suitable for a PEA level study. A summary of the estimated initial capital expenditures, including contingency and any operating costs incurred during the pre-production period, is shown in Table 1-4 and a summary of the estimated deferred and sustaining capital costs, including contingency, are shown in Table 1-5.

The operating cost estimates have an overall accuracy +/-35%, suitable for the PEA level. The life of mine operating costs, excluding capitalized operating costs, were estimated for mining, surface infrastructure, processing, G&A including other costs, realization, and royalties.

Royalties due to Guyana include an 8% royalty on gold sales and a 1.5% royalty on each of silver and copper sales.

The summary of the estimated life of mine operating costs is shown in Table 1-6 and the estimated life of mine unit operating cost estimate is shown in Table 1-7.

Readers are cautioned that this preliminary economic assessment is considered preliminary in nature. It includes inferred mineral resources which are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized and mineral reserves. Therefore, there is no certainty that the conclusions within this preliminary economic analysis will be realised. Mineral resources that are not mineral reserves do not have demonstrated economic viability.

The economic analysis was undertaken to assess and confirm the proposed mine plan described in this technical report, utilizing the production schedule and the associated capital and operating cost estimates included herein. The economic analysis has been conducted on a post-tax, 100% equity (i.e., no debt financing) basis, in constant dollar terms. Sunk costs, such as exploration and the cost of previous studies, were excluded from the analysis.

The economic model incorporates both the historic precious metals purchase agreement with WPMI and the owner operated mining fleet leasing strategy assumed for this study. The WPMI streaming agreement provides for the sale of a portion of the Project’s gold and silver production under fixed-price terms, while the leasing approach reflects the use of an owner-operated fleet financed through OEM-affiliated captive lease programs, which reduces initial capital requirements and ensures consistent equipment availability by maintaining access to new and well-supported equipment throughout the operating period.

The economic viability of the mine plan has been evaluated using key economic indicators, including annual and cumulative cash flows, NPV, and IRR. The NPV presented in this technical report should not be interpreted as the definitive value of the Project and must be considered in conjunction with the accompanying sensitivity analysis.

The key economic results are presented on a pre-tax basis to facilitate comparison with other projects in different jurisdictions by removing the effect of local tax regimes, and on an after-tax basis incorporating the applicable tax rates and economic terms for the Project, providing a more accurate reflection of the potential economic benefits to the Project owners.

The processing facility has been designed with a 7.0 Mtpa capacity. The construction period is scheduled for 12 quarters (3 years). The first mining of mill feed is planned during the first 12 months of Project construction, with all material stockpiled until the process plant is commissioned. The pre-production stockpile is scheduled to supplement run of mine mill feed during Year 1, supporting the rapid production ramp up. Plant throughput will ramp up and reach steady state operations in Year 2. Based on the current mining inventory, the Project has a planned mine life extending to Year 22, providing a long operational horizon and a stable production base following the initial ramp up period.

The total life of mine production is shown in Table 1-8 and the total life of mine metal production is shown in Table 1-9.

The financial analysis utilized the following metal price assumptions for the base case:

These metal prices were selected as being in line with the long term forecasts, as of October 2025.

The results of the economic analysis are summarized in Table 1-10. The NPV at a range of discount rates is shown in Table 1-11.

The sensitivity of the after-tax NPV5%, after-tax IRR, and after-tax payback period to a range of gold prices is shown in Table 1-12.

The result of the economic analysis indicates that the Project is economically viable under the base case assumptions, based on the current mining inventory and the assumptions described herein. At a $3,000 per ounce gold price, the after-tax NPV5% is $1.8 billion, the after-tax IRR is 25.2%, and the payback period is 3.0 years from the start of operations. The economic results are not a measure of the Project’s fair market value.

There are no current exploration or production plans for the Project. Aris Mining has initiated a PFS for Toroparu, targeted for completion in 2026 with a goal of advancing toward construction.

This PEA outlines the technical and economic benefits of the Project and justifies the continuation to PFS level studies.

The mine is designed to produce 7.0 Mtpa of mill feed using conventional open pit methods. The process plant will use a conventional flowsheet to produce doré and copper concentrates for export, containing 5.0 Moz of gold, 4.9 Moz of silver, and 260 Mlb of copper over the life of mine. The oxide processing circuit enables stable operating conditions with predictable reagent use and minimal logistical overhead and provides a low cost, high recovery gold profile for early stage production. The operating cost for the sulphide processing operation is primarily driven by additional power and reagent requirements and high concentrate handling costs, but results in greater overall revenue at moderate incremental cost. The sulphide circuit is competitive with solid metallurgical recoveries and commercially marketable concentrate quality. Both processing routes deliver positive operating margins, confirming the economic robustness of the Project under the current design and energy assumptions. The results reinforce the scalability of the processing plant.

The peak workforce during Project construction is estimated at 1,763. During operations, the peak workforce is estimated at 744. The Project will target a high percentage of the workforce to be hired from within Guyana.

The Project mine life is estimated at 21.3 years based on the current mining inventory. There are opportunities for future mine extension if additional mineral resources are defined through continued exploration.

At the base case assumption of $3,000 per ounce of gold, the Project is estimated to contribute $2.2 billion in income taxes and $1.2 billion in royalty payments to the Guyanese government. The estimated initial capital expenditure is $820 million. The cumulative after-tax net cash flow is $3.9 billion, including initial capital costs, pre-production costs, contingency, construction funding, PMPA financing, other growth capital expenditures, closure, and losses from PMPA financing. Cash costs per ounce of gold are estimated at $826 and AISC per ounce of gold are estimated at $1,289. At the base case assumption of $3,000 per ounce of gold, the Project has an after-tax NPV5% of $1.8 billion, an IRR of 25.2%, and a payback period of 3.0 years.

With the PEA complete, Aris Mining intends to complete a PFS in 2026 with a goal of advancing toward construction.

The qualified person responsible for Section 10 recommends condemnation drilling in the area of planned Project infrastructure to ensure that no potentially economic mineralization underlies the proposed infrastructure. A first pass 400 by 400 m grid is recommended in the areas of the tailings facility, camp area, airstrip, processing plant, and waste dumps. The program will comprise approximately 100 drillholes for 6,000 m, for an estimated cost of $1.5 million.

The qualified person responsible for Section 13 notes that the current PEA has been based on testwork conducted over the past decade using similar, but not identical, samples and objectives. To progress the Project to a Preliminary Feasibility Study level, a comprehensive metallurgical testwork program is recommended to confirm the chosen process criteria for both oxide and sulphide mill feed. The focus of this work should be on the Toroparu deposit, with all testwork performed on representative samples from within the mining schedule to ensure a reliable PFS level design can be further developed.

The recommended studies and testwork include:

The cost to complete this testwork and the PFS is estimated at $1.25 million.

The qualified person responsible for Section 16 recommends the following additional testwork and studies to advance the Project to a PFS level and to support the development of PFS level engineering designs and cost estimates.

The cost to complete the testwork and studies is estimated at approximately $0.7 million.

The cost to complete the testwork and studies is estimated at approximately $0.2 million.

on the saprolite material to assess whether it can be made more impermeable and used as a clay core for the protection levees;

The cost to complete the testwork and studies is estimated at approximately $0.04 million.

The qualified person responsible for surface infrastructure recommends the following work and studies to advance to a preliminary feasibility study:

The cost to complete this testwork is estimated at $1 million.

The qualified person responsible for the tailings management facility recommends the following work and studies to advance to a preliminary feasibility study:

The cost to complete this testwork is estimated at $1.5 million.

The qualified person responsible for Section 20 makes the following recommendations:

This work can be undertaken as part of the future Project permitting work and will be accounted for within the existing environmental budget.

This technical report has been prepared for Aris Mining in compliance with the disclosure requirements of NI 43-101 to disclose material changes to the Project resulting from updated mineral resource estimates and the results of a PEA.

The effective date of this technical report is October 21, 2025. No new material information has become available between this date and the signature date given on the certificate of the qualified persons. The quality of information, conclusions, and estimates contained in this technical report is based on information available at the time of the effective date and the assumptions, conditions, and qualifications set forth in this technical report. Except for the purposes legislated under Canadian securities law, any other uses of this technical report by any third party is at that party’s sole risk. The user of this technical report should ensure that this is the most recent technical report for the Property and that it has not been superseded by a new technical report. Any previous technical reports for the Project are no longer current.

Aris Mining is a Canadian mining company with its common shares listed on the Toronto Stock Exchange under the symbol ARIS and the NYSE American LLC under the symbol ARMN.

Unless otherwise stated, information, data, and illustrations contained in this technical report or used in its preparation have been prepared by the authors for the purpose of this technical report.

This technical report was prepared by Vaughn Duke, Pr. Eng., Founding Partner and Director of Sound Mining International Limited; Jan Eklund, P.E., Process Consultant of LogiProc Pty. Ltd. (LogiProc); and Pamela De Mark, P. Geo., Senior Vice President of Geology and Exploration of Aris Mining, all of whom are Qualified Persons as defined by NI 43-101 and are independent of Aris Mining for the purpose of NI 43-101, with the exception of Pamela De Mark, who is an employee of Aris Mining. The qualified persons for the technical report and sections for which each qualified person is responsible are presented in Table 2-1.

Mr. Duke conducted a personal inspection of the Project from June 10 to 12, 2025. Mr. Duke reviewed the proposed locations of the open pit operation, the processing plant, and tailings management facility, as well as the environmental setting, road access, and logistics for mining.

Mr. Eklund did not conduct a personal inspection of the Project.

Ms. De Mark conducted a personal inspection of the Project from June 10 to 12, 2025, and from July 4 to 6, 2025. During the visit Ms. De Mark reviewed representative core intersections across the deposits, reviewed the core cutting and storage facilities, and reviewed the site layout and logistics for future mining and processing and the environmental layout.

Unless expressly stated otherwise in this technical report, all currency amounts are in United States Dollars and quantities are in metric units. Project data coordinates are in the Universal Transversal Mercator (UTM) grid Zone 20N: 1956 Provisional South American Datum.

In preparing this technical report, Pamela De Mark has relied on information provided by employees of Aris Mining in 2025, regarding environmental and permitting matters described in Section 20. The qualified person has not independently verified this information and disclaims responsibility for such information used in Section 20.

Except for the purposes legislated under applicable securities laws, any use of this technical report by any third party is at that third party’s risk.

The Property is located in the Cuyuni-Mazaruni Region of Guyana, approximately 215 km southwest of the capital city of Georgetown, at approximately 6°27′1″ N and 60°3′11″ W. A map showing the location of the Property is shown in Figure 4-1 (source: Aris Mining, 2025).

The Project is 100% owned by Aris Mining through its indirect, wholly owned subsidiary, ETK.

A summary of the Upper Puruni Concessions is provided in Table 4-1, a map showing the location of the titles is shown in Figure 4-2 (source: Aris Mining, 2025), and a list of the Project titles is provided in Appendix A. Mineral properties in Guyana allow for four scales of operation. ETK holds or has applied for each of the four types of titles, including MPs, PPMSs, and Small Scale Claims, and two open PL applications which have been with the GGMC for approval since February 2020. Rentals on the claims and permits controlled by ETK are payable annually by the expiry date of each claim and permit. A work performance bond equal to 10% of the approved budget is required for mining licenses.

The four scales are defined as follows:

$0.50 per acre for the fourth and fifth years. Large areas for geological surveys are granted as Permission for Geological and Geophysical Surveys with the objective of applying for PLs over the favourable ground.

The Toroparu deposit is located on property that was originally subject to the Mining Joint Venture Agreement which documented the terms and conditions of the Alphonso joint venture, then known as the Upper Puruni Venture (the Mining Joint Venture Agreement). The Mining Joint Venture Agreement was entered into between Mr. Alfro Alphonso and Mr. Gregory K. Graham effective August 1, 1999. This original agreement was amended and restated in its entirety effective January 1, 2008 pursuant to the terms of an amended and restated joint venture agreement between Mr. Alfro Alphonso and ETK (the A&R Joint Venture Agreement).

In March 2020, ETK exercised its option under the A&R Joint Venture Agreement and acquired the Option Interest excepting and reserving only to Mr. Alphonso the right to conduct the alluvial mining activities on certain lands not associated with the Project, as set out in the A&R Joint Venture Agreement, and the use by Mr. Alphonso of certain roads and an airstrip constructed by ETK. ETK paid $20 million to exercise the option to acquire the Option Interest and extinguish its obligations to make further payments under the A&R.

In connection with the option exercise, Mr. Alphonso delivered to ETK a written affirmation, declaration of trust and receipt acknowledging that he hold all lands and permits subject to the A&R Joint Venture Agreement in trust for the exclusive benefit of ETK until such time that the GGMC and the Minister of Natural Resources of Guyana convert the Small Scale Claim licenses and MPs that are subject to the A&R Joint Venture Agreement to large scale Mining Licenses, and the same are issued in the sole name of ETK. ETK is required to pay any and all costs, including any fees or rentals, associated with such lands and permits. Mr. Alphonso further acknowledged that he is obligated to take any such action as may be reasonably requested by ETK, the GGMC or the Minister of Natural Resources to complete such conversion.

The Sona Hill deposit is located on property that is subject to the Godette joint venture (the Godette Joint Venture). Through its wholly owned subsidiary ETK, Aris Mining has rights to four MPs (the Godette MPs) pursuant to the joint venture agreement effective April 1, 2008 (the Godette Agreement). ETK has sole operatorship and sole decision-making discretion in all matters pertaining to gold exploration on the lands subject to the Godette Agreement. ETK also has the sole and exclusive right to sell all gold, other precious metals, or gemstones it may recover from the properties. On December 21, 2012, ETK purchased 100% of the Godette’s’ interest in the Godette Agreement for $300,000. The Godette Heirs remain the registered owner of the Godette MPs; however, under the Godette Agreement, the Godette Heirs have irrevocably contributed and committed all their right, title, and interest in the Godette MPs for the benefit of ETK and the Godette Joint Venture and have granted ETK the exclusive right to conduct operations. Further, the Godette Heirs have agreed that during the term of the Godette Agreement, the Godette Heirs will not deal or attempt to deal with any right, title, or interest in the Godette MPs or in their interest in the Godette Agreement in any way that would or might affect the right of ETK to conduct operations on the lands subject to the Godette MP. Finally, the Godette Heirs have agreed to execute such documents and agreements and take such actions as are reasonably necessary to assist in the conversion of the Godette MPs to large scale mining licenses which shall be issued solely in the name of ETK.

ETK holds an irrevocable power of attorney from the Godette Heirs, providing ETK, with among other powers, the right to take any action that the Government of Guyana may require to issue a Mining Permit covering the Godette MP’s.

The Toroparu PMPA refers to the amended and restated precious metals purchase agreement among WPMI, Aris Mining Toroparu Holdings Ltd. (formerly GoldHeart), a wholly-owned subsidiary of Aris Mining, and Aris Mining Guyana Holdings Corp. (formerly Sandspring, an indirect, wholly-owned subsidiary of Aris Mining) dated April 22, 2015.

WPMI originally entered in the Toroparu PMPA in 2013, which was subsequently amended in 2015, at a time when the Project was owned by Sandspring Resources, a single-asset junior developer. Under this terms of the PMPA, WMPI may elect to provide $138 million in construction funding following completion of a full development plan, in exchange for the right to purchase 10% of Toroparu’s gold production and 50% of its silver production at fixed prices of $400/oz and $3.90/oz, respectively, with both prices subject to escalation beginning on the fourth anniversary of commercial production. The capital commitment represented approximately 30% of the $464 million project finance required as determined in the 2013 PFS.

WPMI has made initial payments totalling $15.5 million, with the remaining $138.0 million to be paid in instalments during construction of the Toroparu Project, subject to WPMI’s election to proceed following receipt of a final feasibility study for the Toroparu Project, environmental study and impact assessment and other Project related documents.

The parties intend to explore opportunities for amending the terms of the agreement to align with the updated project parameters.

The Consulting Agreement between ETK and A&S was executed on November 1, 2013, and which survived the exercise by ETK of the option under the A&R Joint Venture Agreement as described above. Pursuant to the Consulting Agreement, A&S is to be paid, commencing on the first anniversary of ETK receiving cashflow sufficient to develop and construct a conventional open pit mining and flotation and cyanide leach process operation on the Property with on-site and off-site support operations (with such cash flow to be determined in a definitive feasibility study), eight annual payments of a minimum of $1.0 million adjusted upwards in accordance with the indexing formula set out in the Consulting Agreement (to

a maximum of $2.0 million), followed by five extended payments of a maximum of $1.0 million (provided the daily price of gold averaged over a twelve-month period or a calendar month period, as applicable, exceeds $1,750 per ounce) subject to downward indexation based on a formula set out in the Consulting Agreement. Using the base case gold price of $3,000 per ounce applied in this study, the aggregate amount payable to the consultant under the Consulting Agreement is estimated at $21 million.

ETK is a party to a Mineral Agreement with the Government of Guyana that details all fiscal, property, import-export procedures, taxation provisions, and other related conditions for the continued exploration and future mine development and operation of an open pit mine at Toroparu. The Mineral Agreement implements a two-tiered gold royalty structure of 5% of gold sales at gold prices up to $1,000 per ounce and 8% of gold sales at gold prices above $1,000 per ounce, as well as a royalty of 1.5% on sales of copper and other valuable minerals.

To the extent known, there are no other royalties, back-in rights, payments, or other agreements and or encumbrances to which the Property is subject.

The most significant environmental issue within the Project area relates to the disturbance caused by historic and on-going illegal artisanal and small scale mining activities. These activities have altered portions of the Wynamu and Puruni river channels and banks within the Project. Abandoned artisanal mining pits containing stagnant water have also created conditions conducive to the proliferation of malaria carrying mosquitoes. Baseline soil chemistry assessments completed in 2022 on historical artisanal tailings within the Project area identified elevated mercury concentrations.

To the extent known, there are no environmental liabilities to which the Property is subject.

ETK holds all the necessary permits and permissions currently required to conduct its exploration work and medium-scale mining and gravity recovery of gold and other minerals on the Project. In order to advance the Project, ETK has applied to the GGMC and the Minister of Natural Resources of Guyana to convert the Small Scale Claim licenses, Mining Permits and Prospecting Permits it presently holds through the A&R Joint Venture Agreement and the Godette Agreement to large scale mining licenses and to issue the same in the name of ETK (the Conversion).

ETK has a renewed environmental permit for the Project effective for the period between October 2024 and September 2029. The environmental permit must be renewed by submitting a completed Application Form for Renewal of Environmental Authorization to the Environmental Protection Agency of Guyana no later than March 31, 2029. Following the filing of this PEA, ETK will undertake the normal course notifications and consultations with the EPA before commencing construction, ensuring that the existing permit is updated to reflect the final Project plans.

The Ministry of Natural Resources of Guyana and the Ministry of Public Infrastructure of Guyana (the Ministries) have also settled on the terms of a road users’ agreement to be entered into upon completion of the Conversion, wherein, among other things, the Ministries will facilitate any arrangements that are required by ETK in order to enjoy unhindered and reasonable access to a road built on public lands leading to the Project and ETK will maintain and rehabilitate sections of such road, subject to the final terms of such agreement.

ETK has negotiated the terms of an Investment Agreement with GO-Invest which governs the terms by which the Company, directly or indirectly through contractors, undertake the activities as set out in the Mineral Agreement such as importing vehicles, machinery, equipment and materials required for building the Project and also governs the terms by which the Guyana Revenue Authority will extend certain tax exemptions. It is expected that ETK and GO-Invest will enter into the Investment Agreement once the Conversion is complete.

Aris Mining is not aware of any other significant factors or risks that may affect access, title, or the right or ability to perform on-going work programs on the Property.

The topography is flat to gently undulating to hilly, with elevations ranging from 80 to 170 m above sea level at the Toroparu deposit and from 80 to 135 m above sea level at the Sona Hill deposit. In places there are hills with steep relief.

The Project is located within a poorly drained tropical rain forest characterized by dense vegetation. Vegetation has been cleared in the areas developed for the current site infrastructure, including the camp, airstrip, and access roads.

Weather records are based on data measurements collected from a meteorological base station established during baseline environmental studies in 2007, and two regional weather stations managed by the Guyanese Hydrometeorological Agency at Mazaruni, located 200 km from the Project, and at Enachu, located 75 km from the Project. The average temperature on site is around 28°C with a minimum of 18°C and a maximum of 32°C. Humidity is high with an average of 82%, with values ranging from between 64 and 100%. Annual rainfall ranges from 2,000 to 3,500 mm with two wet seasons occurring between December to February and between May to July. The dry season is the ideal time to carry out geochemical sampling, drilling, and geophysical surveys, but exploration can be carried out on a year-round basis. The same is assumed for any future mining operations.

Road access to the Property from Georgetown is via 110 km of paved highway south to the town of Linden, then 18 km of public gravel road to Bartica, a ferry crossing of the Essequibo River at Bartica to Itaballi, then 200 km of public gravel road to the south gate at Toroparu Junction, then 25 km north to the Project site. Overland travel time is approximately 10 to 12 hours in the dry season. ETK is exploring possible partnerships with other road stakeholders to coordinate road maintenance and stewardship and is working on a road use and maintenance agreement with G Mining Ventures for the Itaballi to Puruni Landing section of the road.

The Project can also be accessed via a one hour, 220 km charter flight from Ogle Airport in Georgetown to the 650 m long airstrip at the Project, which can accommodate Cessna Caravan flights holding up to 13 persons or 1,200 kg of cargo. The Project airstrip is licensed and certified by the Guyana Aviation Agency.

Equipment and supplies come from Georgetown. Heavy equipment and cargo may be transported by small ocean-going vessels and barges on the Essequibo River to Itaballi, then loaded on to trucks for the 230 km overland journey to Toroparu, crossing the Puruni River at the town of Puruni Landing, located approximately 60 km from Itaballi, on a company operated 40 tonne ferry barge. ETK maintains and operates the Puruni River pontoon crossing.

Heavy equipment operators are available from Georgetown, which has a population of around 235,000, and the town of Linden located approximately 110 km south of Georgetown, which has a population of approximately 45,000, and from other population centres in Guyana. The nearest population centre is at Bartica, which is located 230 km away from the Project and has a population of approximately 11,000.

ETK is the beneficial holder of all right, title and interest in the lands subject to the Project and therefore also has all surface rights. The titles are also covered by logging concessions that allow the concession holder the right to remove any merchantable timber when the Property is cleared of vegetation for Project development.

ETK has initiated the acquisition of land leases from the Guyana Lands and Surveys Commission for the Project off site facilities, including the proposed port facility at Pine Tree Landing located near Itaballi, the Itaballi landing facility, and the Itaballi laydown support facility at Aremu Junction.

The Property has sufficient area to allow for future tailings management areas, waste disposal areas, and processing plant sites.

The current Project infrastructure includes the camp, kitchen and mess hall, gym, security fencing and checkpoints, maintenance and welding workshops, carpentry shop, warehouse, water pump and water tank, freshwater pond, core sheds, drilling contractor’s facilities, a 650 m long unpaved airstrip that can accommodate Cessna Caravan flights holding up to 13 persons or 1,200 kg of cargo, diesel generators and a 70,000 litre capacity fuel farm, and satellite internet.

The Project camp can accommodate up to 200 persons and has an onsite health centre staffed by qualified medics. The health centre is equipped to provide emergency first response clinical care for employees, the provision of mosquito bed nets, malaria treatment, and daily checks of blood pressure, blood oxygen, and sugar levels. The centre also provides health care assistance to sick camp visitors as well as emergency evacuations via a 24 hour standby medivac flight in the event of a serious injury.

ETK also owns additional facilities along the Puruni road. At Itaballi Landing, there is a security outpost with a water pump and tank, and a wharf for the transport of people and materials by fast boats. At Itaballi Camp, located 3 km along the Puruni road, there is a camp facility to accommodate 45 people, a kitchen and mess hall, gym, maintenance workshop, warehouse, water well and pump, health post, security fencing and checkpoint, a diesel generator and 30,000 litre capacity fuel farm, and internet. At Puruni, located 100 km along the Puruni road, there is a pontoon for crossing people, vehicles, and equipment across the Puruni River, and accommodation for three people in a house located within G2 Goldfield’s Peter’s Mine compound. At Camp 106, located 106 km along the Puruni road, there is a camp facility to accommodate 30 people, a kitchen and mess, a diesel generator, and water well and pump. At Toroparu Camp 4, located 200 km along the Puruni road, there is a security outpost and gate, satellite internet, and a water well and pump.

Water is available through the year from the Wynamu River, its creeks, and from rainfall run off. Water for the camp is available throughout the year from a groundwater fed supply pond, supply wells, and from rainfall run off.

During commissioning, all plant water will be pumped at a rate of 561 litres per second from the Puruni River, and during operations the demand will drop to 53 litres per second. The water will be pumped to the process plant for use as reagent make-up, potable water, gland water, and process water.

The peak make up water demand for mining is 359,334 cubic metres per month and can be sourced from rainwater harvesting, abstracted from the Puruni and or the Wynamu rivers, as well as boreholes. Excess contact and mine water will be managed and treated if required before being discharged to the environment.

There is no nearby power grid. The estimated power requirements for the planned process plant are approximately 50 MW, which will be supplied by a 50 MVA, 13.8 kV onsite heavy fuel oil power plant. The plant will consist of six generator sets rated at 9.28 MW, configured to provide an operational capacity of 46MW and an installed capacity of 55 MW, including one standby unit. The generating sets will comprise a four-stroke, V-type, 16 cylinder, turbocharged, and intercooled diesel engine capable of operating on heavy fuel oil, marine diesel oil, or light fuel oil.

The fuel system will manage the unloading, storage, treatment, and delivery of heavy fuel oil transported by road from Georgetown to the Project. Deliveries will be made using four daily 50,000 litre (50 cubic metre) capacity fuel tankers to sustain continuous operations at full load. The power plant’s average fuel consumption will be approximately 196 cubic metres per day. The site fuel storage system will consist of two main heavy fuel oil storage tanks, each with a 2,200 cubic metre capacity, providing approximately three weeks supply of full load operation.

Power will be distributed by overhead power line to the primary crushing area, tailings facility, as well as the open pit mine, accommodation area, and the main access gate.

The first known gold mining in the Project area was by alluvial mining methods around 1887. Regional and local mapping was undertaken in 1950. Mr. Alphonso began mining old tailings and river alluvium at Toroparu in 1997 using high pressure water jets to wash the material into a pit and then pumped the slurry up to a sluice box. The alluvial material was mostly exhausted by 1999 and work proceeded deeper into the underlying saprolite, which eventually developed into the Toroparu saprolite open pit. This operation, which utilized up to 15 dredges, continued until 2001.

Exploration by ETK at Toroparu began in 1999 with the Alphonso Joint Venture, which named ETK as the Project operator.

Between 1999 and 2018, ETK conducted extensive auger drill sampling campaigns around the Toroparu saprolite open pit and on a regional scale for the purpose of evaluating the possibility of re-working the mine tailings, to test the saprolites beneath alluvial cover in areas of historic gold workings, to determine regional gold potential, and to identify surface mineralization for follow up by diamond drilling. Geochemical and trench sampling and geophysical surveys were also conducted during this period to identify gold mineralization targets.

In 2000, ETK commenced rehabilitation and upgrade of the 240 km access road into the Property.

In 2004, ETK commissioned a gravity circuit to test mine the tailings and saprolite and conducted intermittent, seasonal test mining from saprolite at the saprolite open pit from late 2004 to early 2007 using hydraulic sluicing and a gravity circuit with screens, ball mill, centrifugal concentrators, and shaker tables.

The first diamond drilling on the Property began in late 2006, comprised of 23 drillholes that identified gold mineralization over a volume of 600 by 300 by 300 m around the Toroparu saprolite open pit. In 2008 a further seven drillholes were completed, which expanded the known mineralization to 650 by 350 by 425 m. The first mineral resource estimate was prepared effective October 26, 2008, utilizing 27 drillholes for 9,492 m.

In 2009, ETK conducted an initial metallurgical scoping test program from saprolite and hard rock samples collected from core from the Toroparu deposit, in order to assess the amenability of the saprolite and bedrock for typical gold and copper recovery.

On November 24, 2009, Sandspring acquired 100% of GoldHeart, which through its wholly owned subsidiary ETK held the mineral and prospecting rights to the Project and adjacent properties.

Sandspring began a diamond drilling program in 2010 for resource definition and infill of the main mineralization zone, to step out drilling to the east-southeast, west-northwest, and west of the Toroparu saprolite open pit, and to expand and upgrade the mineral resource categories of mineralization identified in previous drill programs. Five geotechnical drillholes were completed for pit slope geotechnical design. Sandspring also conducted geophysical surveys over the Toroparu deposit and reconnaissance grids over the Ameeba, Manx, and Timmermans prospects.

Sandspring completed two mineral resource estimates in 2010, effective May 12, 2010, and September 12, 2010.

In 2010, CM Power Inc. undertook an evaluation of the hydro power capacity of the Kumarau Falls on the Kumurung River, which was a former United Nations Development Program sponsored project, located 35 km southwest of the Project.

In 2011, Sandspring conducted a mineral resource definition diamond drilling program focussed on the eastern main mineralized zone of the Toroparu deposit to increase the mineral resources and to upgrade inferred mineral resources to measured and/or indicated resources. This work identified the main lithologies and controls on mineralization. By this time the drilling database contained 225 drillholes for 111,668 m completed between 2006 and 2011. Additional drilling was conducted later in 2011 adjacent to the main zone area to explore for nearby satellite deposits, as well as reconnaissance

drilling over prospective areas with promising surface exploration results, including Ameeba and Manx, located several kilometres to the northwest and northeast of the Toroparu deposit, respectively.

Sandspring prepared an updated mineral resource estimate and PEA of the Toroparu deposit effective April 30, 2011, utilizing drilling data available up to December 31, 2010. A PFS level pit slope design report was prepared in October 2011.

Other exploration work conducted by Sandspring in 2011 included a regional saprolite geochemistry sampling program focussed on high gold potential areas and semi-regional and detailed geochemical sampling where alluvial mining activities showed gold potential, geophysical surveys over several gold prospects including Ameeba, Timmermans, Manx, and northwest of the Toroparu deposit to complete the 2010 grids, and a LIDAR survey to produce a detailed topographic contour map. Additionally, SGS completed a metallurgy gold deportment study for Sandspring on a 400 kg composite sample of the Toroparu mineralization collected from 23 diamond drillholes, to determine gold occurrences and to identify and evaluate any mineralogical factors that might affect gold recovery.

In mid-2011 the access road to the Project was improved and rehabilitated over a total distance of 240 km. A road work contract was signed with the GGMC in 2012 to finance part of the total road rehabilitation costs. Approximately 100 km of the road rehabilitation work was conducted by a local construction company.

Sandspring signed a Mineral Agreement on November 9, 2011 with the Government of Guyana, which defined all fiscal, property, import-export procedures, taxation provision, and other related conditions for the continued exploration, mine development, and mining and processing operations at the Property. The Government of Guyana agreed to grant a large scale mining license which allows the start of commercial production once economic feasibility is demonstrated.

In 2012, 142 holes were completed for the Toroparu deposit area, bringing the drilling database to a total of 367 holes for 145,723 m completed between 2006 and 2012. Sandspring completed an updated mineral resource estimate and PEA of the Toroparu deposit, effective January 30, 2012, utilizing the drilling data available up to October 2011.

Exploration work in 2012 included regional and detailed auger sampling to assess regional gold potential and to identify local gold anomalies, geochemical sampling surveys, and re-analyses of previous geophysical survey data. Reverse circulation drilling was also conducted to test gold anomalies identified by the saprolite geochemistry samples. The results for Ameeba were limited. Sandspring also conducted reverse circulation and diamond drilling at Sona Hill, which showed encouraging but scattered gold intercepts with no significant copper.

Project work in 2012 included a preliminary design study on the access road reconstruction from the Itaballi port facility to the Project, a distance of 230 km, including a conceptual roadway reconstruction design plan, cost estimates, and preliminary solicitation of qualified contractors. In June 2012 the environmental permit was granted by the Environmental Protection Agency. A monitoring program commenced to assess the upstream and downstream Kumurung River flow characteristics as well as rainfall in the Project watershed.

In 2013, Sandspring completed a mineral resource estimate and the first mineral reserve estimate for an open pit project as part of a PFS effective May 8, 2013.

Following the 2013 PFS, Sandspring continued to conduct exploration to evaluate other areas on the Property, including auger and soil sampling of regional targets, past and current alluvial gold prospecting, and by exploration diamond drilling. This work included infill saprolite sampling at Sona Hill prior to diamond drilling. The Wynamu Hill gold anomaly was discovered by geochemical surveys in 2012 and 2013.

Three diamond drilling programs comprising 184 holes for 21,963 m were conducted at Sona Hill in 2015, 2016, and 2018, which were utilized for the first mineral resource estimate for Sona Hill, effective September 20, 2018. Other work at Sona Hill included geochemical sampling and geophysical surveys conducted between 2015 and 2016.

Sixty-two diamond drillholes were also completed at the Wynamu exploration target in 2016 and 2018, with promising results. In 2018, additional diamond drilling was undertaken at Ameeba focussed on saprolite hosted gold mineralization, which returned narrow and scattered results.

Sandspring changed its name to Gold X on November 29, 2019. A diamond drilling program was undertaken in 2020 and 2021, consisting of 114 holes for 20,750 m at the Toroparu main and southeast areas to test a new geological interpretation of narrow, cross-cutting high grade structures, compared to the previous interpretations of a large, low-grade deposit.

On June 4, 2021 Gran Colombia acquired all of the issued and outstanding shares of Gold X, and indirectly, the Project. On November 29, 2021 Gran Colombia changed its name to GCM Mining.

In June 2021, GCM Mining began refining the Project development options. GCM Mining completed an updated mineral resource estimate and PEA on the Project, effective December 2, 2021, utilizing drillholes and trenches completed between 2006 and 2021 for the Toroparu and Sona Hill deposits.

GCM Mining began pre-construction activities in 2021, including hiring the Project team and key contractors, preparation of camp facilities, rehabilitation of the Project airstrip, design and civil works related to the camp, road, and water management, electrical network design, permitting, design of initial environmental and social governance initiatives, and various environmental studies. Following the 2021 PEA, GCM Mining undertook additional infill drilling, prepared for a PFS, and worked with the local governmental agencies to finalize the amended mining license for a large-scale mining license incorporating an open pit and underground mine operating plan as outlined in the 2021 PEA.

On September 26, 2022, Aris Gold Corporation completed a business combination with GCM Mining, and the combined entity was renamed Aris Mining. Aris Mining indirectly holds 100% of the Property through its wholly owned subsidiary, ETK. Following the business combination, Aris Mining started a re-evaluation and optimization process for the Project, and reduced the previously planned expenditures until such time as the development plan is fully defined. As part of this review process, Aris Mining undertook a new detailed structural analysis and updated geological model and prepared an updated mineral resource estimate effective February 10, 2023.

In 2024, Aris Mining advanced optimization studies focussed on power and site access options, and in 2025 commenced this PEA.

The first mineral resource estimate for the Project was completed by ETK effective October 26, 2008. Mineral resource estimate updates were prepared by Sandspring effective May 12, 2010 and September 12, 2010. The first PEA was completed by Sandspring effective April 30, 2011. This was followed by an updated mineral resource estimate and PEA by Sandspring effective January 30, 2012. An updated mineral resource estimate was completed by Sandspring effective March 31, 2013, and a PFS to support the first mineral reserve estimate was completed by Sandspring effective May 8, 2013. An updated mineral resource estimate was completed by Sandspring effective September 20, 2018, and a PEA was completed by Sandspring effective June 11, 2019. This was followed by an updated mineral resource estimate and a PEA by GCM Mining (renamed to Aris Mining) effective December 1, 2021. The most recent historical mineral resource estimate was by Aris Mining and effective February 10, 2023.

None of these historical estimates and studies are considered to be current and should not be relied upon.

Historical gold production from the Project has been from shallow alluvial and saprolite mining and placer processing of free gold. Undocumented small-scale sluice and riffle table processing of alluvium and shallow lag gravels continues to the present day. There are no records of the gold production.

ETK undertook intermittent, seasonal test mining between late 2004 to early 2007 from the saprolite open pit using hydraulic sluicing and a gravity circuit with screens, ball mill, centrifugal concentrators, and shaker tables. There are no records of the gold production.

The Project is located in the northern half of the Amazonian Craton of the Guiana Shield and is mainly underlain by supracrustal Paleo-Proterozoic aged volcano-sedimentary belts and large granitoid batholiths of the Barama-Mazaruni Supergroup. These belts form the northwest trending Puruni volcano-sedimentary belt comprised of basal mafic tholeiitic basalts and minor ultramafic rocks overlain by alternating mafic to intermediate volcanic rocks and sedimentary rocks, generally metapelites and greywackes. The Puruni volcano-sedimentary belt extends between the Aurora batholith to the north of the Project and the Putareng batholith to the southwest. The Putareng batholith corresponds to a calc-alkaline intrusive complex with small, elongate intra-belt plutons. The Toroparu and Sona Hill deposits are developed along the contact of one of these small intrusive bodies. Other gold deposits in Guyana related to similar intrusive bodies include Aurora, located approximately 50 km to the northeast of Toroparu, Oko and Oko West, located approximately 140 km to the east, and Omai, located approximately 180 km to the southeast. Younger irregularly shaped mafic intrusions are widespread in the area. The northwest trending features follow lithological contact zones and show a sigmoidal flexure zone to the northwest of the Project. The Toroparu deposits occur close to the crossing of the west-northwest trending Puruni lineament and the north-northwest trending Wynamu lineament, as shown in Figure 7-1 (source: Aris Mining, 2025).

The Toroparu and Sona Hill deposits are hosted in a sequence of meta-sedimentary and meta-volcanic rocks in a greenstone belt between Proterozoic granitoid batholiths. A plan of the local geology is shown in Figure 7-2 (source: Aris Mining, 2025).

Regional aeromagnetic-radiometric lineament data indicates the presence of major folds that are likely to also occur at a smaller, deposit scale. The upright fold axial planes appear to strike northwest and plunge both northwest and southeast, as shown in Figure 7-3 (source: Pratt and Smeraglia, 2022). Local aeromagnetic data show similar curved magnetic lineaments and probable folds with an interpreted northwest to west-northwest strike and plunging both northwest and southeast. It is possible that Toroparu is located along a northwest striking and southeast plunging fold. Sona Hill is located along north trending and west dipping lithologies and structures. Evidence of folding is widespread in the geophysical data, drillhole data, and rare surface exposures.

Mineralization at the Toroparu deposit has been intersected in drillholes for up to 2.5 km along strike, up to 250 m across strike, and up to 600 m in depth, and at Sona Hill for up to 900 m along strike, up to 250 m across strike, and up to 300 m in depth. Recent structural interpretation work indicates that the main body of mineralization at Toroparu is likely part of a major regional fold structure striking west-northwest to northwest, with a distinct sigmoidal shape and higher gold grades within the bend (Pratt and Smeraglia, 2022). Folding and ductile deformation resulted in a west-northwest to northwest striking schistosity and parallel mineralized veins, dykes, and shear zones.

Thin, discontinuous mineralized shear zones at the Toroparu deposit are developed mainly in volcanic rocks. Higher grade, discontinuous shear zone hosted mineralization is narrow and mostly parallel to the schistosity. The main controls on mineralization are the west-northwest striking axial planar schistosity and vein swarms that are well developed in the volcanic rocks, and the folded contact between an intrusive complex and volcanic rocks, particularly the contact of an igneous breccia that forms an important rheological contrast, similar to many other orogenic gold deposits that are strongly controlled by competency contrasts. The Toroparu deposit dips roughly 55° to the west. The Sona Hill deposit has similar controls on mineralization but strikes to the north and dips around 30° to the west.

Two dyke phases are present including hornblende porphyritic andesite dykes and dolerite dykes. Most dykes have an apparent thickness of less than 0.5 m, but some dykes up to 2.5 m thick also occur. The hornblende porphyritic andesite dykes are weakly to intensely deformed with schistosity roughly parallel to that of the host rock. In places, these dykes are folded. Despite being sheared and folded, the dykes are mostly non-mineralized, although some mineralized veins occur along the contacts. Some of these dykes are cut by mineralized shear zones. The dolerite dykes are fine grained, non-sheared, and non-mineralized. They crosscut gold mineralized veins, silicified zones, and shear zones and postdate both the deformation and the gold mineralizing events. The dykes are less abundant and more discontinuous at Sona Hill compared to Toroparu.

A thick, gradational, 10 to 35 m thick layer of saprolite with preserved mineralized quartz veins and veinlets, showing evidence of some gold leaching, is present at the surface at Toroparu and reaches up to 60 m thick at Sona Hill. A weathering profile comprised of overburden, saprolite, and a transition zone has been interpreted for the mineral resource estimate. The overburden has abundant low grade gold mineralization but little high grade.

A plan of the property geology is shown in Figure 7-4 (source: Aris Mining, 2025).

Mineralization at the Toroparu deposit estimated as mineral resources in the main zone has a volume of around 1.3 km along strike, around 500 m across strike, and a depth of 550 m. There is a zone of mineral resources approximately 1.1 km to the southeast of the main zone with a volume of around 400 m along strike, 230 m across strike, and a depth of 250 m. There are a few other small zones of mineral resources on the order of 100 m long along strike of and parallel to the main zone. The mineralized shear zones are narrow and discontinuous. Sona Hill has a volume of around 950 m along strike, up to 300 m across strike, and a depth of around 200 m. Sona Hill is characterized by a lower copper content compared to Toroparu. Both deposits are open at depth.

The main body of mineralization at Toroparu is characterized by three different vein assemblages including:

Local gold mineralized silica alteration occurs as discrete patches or as zones up to tens of metres thick that affect volcanics, intrusives, and igneous breccias. In places the silica is associated with epidote. Silica alteration is characterized by disseminated chalcopyrite and is crosscut by quartz chalcopyrite veins and chalcopyrite veinlets. In contrast with the

schistose rocks, the veinlets have an apparent random orientation. Silica alteration halos occur around the chalcopyrite veinlets and have higher gold grades.

Plans of the Property gold and copper mineralization interpretations are shown in Figure 7-5 (source: Aris Mining, 2025).

The mineralized veins are folded, sheared, transposed, and boudinaged, and are rotated by shearing parallel to the schistosity in both volcanic and intrusive rocks. Mineralized veins, shear zones, schistosity, and the hornblende porphyritic andesite dykes show a consistent west-northwest to northwest strike and moderate to steep southwest dip, consistent with the regional northwest strike of folds interpreted from the aeromagnetic data. This fractal similarity suggests that the main pit mineralization is part of a major regional fold structure. It is likely that these folds are tight, and most limbs and contacts are parallel to schistosity. Fold areas may be areas of high grade and likely have a shallow plunge and present an exploration target. Figure 7-6 (source: Pratt and Smeraglia, 2022) shows a schematic structural model for Toroparu in the main zone area.

Shear zones with a distinctive intense schistosity and sigmoidal shape ranging in thickness from 0.1 m to up to a few metres are common in the Toroparu main pit area, especially in the volcanic rocks. Gold mineralized quartz and chalcopyrite veins are sheared, transposed to parallel and are folded along the shear zones. Some of the shear zones are flooded by silica alteration. Non-mineralized shear zones are characterized by smectic and carbonate, possibly ankerite. Most of the gold mineralized veins, shear zones, non-mineralized shear zones, schistosity, and bedding show a northwest strike and a steep to moderate southwest dip.

The main tectonic event in the Toroparu area is interpreted to be regional folding of volcanic rocks and a pre-existing intrusion. Folding and shortening rotated the mineralized veins and hornblende porphyritic andesite dykes parallel with schistosity. Mineralized veins may have initially formed as tension gashes in the early stages of deformation. A flattened, deformed porphyry vein system is another possible interpretation. Continued folding and flattening rotated the veinlets, resulting in shearing, transposition, and boudinage along schistosity. When shortening intensity reached a critical point and the folds locked, shear zones developed, possibly under a transpressional stress regime. The timing of the silica alteration event is uncertain but is associated with higher gold grades. Finally, non-deformed and non-mineralized dolerite dykes crosscut the folds. They are considered too thin to significantly dilute the gold resource.

The interpretation of the deposit type at Toroparu is uncertain, with possibilities including an unusually copper rich orogenic gold deposit on the basis of the host greenschist metamorphic rocks and a strong control of mineralization due to competency contrasts, as well as a metamorphosed porphyry gold-copper deposit. Recent structural interpretation work suggests that Toroparu is not a classic lode type orogenic gold deposit and is unlikely to be a deformed porphyry deposit (Pratt and Smeraglia, 2022). A disseminated or sheeted vein type deposit can be used as a guide for exploration planning purposes.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The first activity at the Project was alluvial placer mining by Mr. Alphonso that commenced in 1997. ETK began exploration in 1999, and following the Mining Joint Venture Agreement with Mr. Alphonso in 2000, commenced rehabilitating and upgrading the 240 km access road into the Property to facilitate the transport of mining equipment and supplies.

Systematic exploration activities at Toroparu commenced in 2011 and include mapping, surface geochemical sampling, near surface auger drilling, geophysical surveys, reverse circulation drilling, and diamond drilling. The surface sampling initiated on a wide grid spacing and was tightened around areas of interest, and was utilized, along with initial reverse circulation drilling, to identify high value targets for diamond drilling. The geochemical sampling work identified geochemical markers for specific lithological units and the geophysical surveys showed that magnetic highs overlap the mineralized zones. The geochemical sampling identified the Toroparu northwest area, Sona Hill, Sona Hill South, Majuba located to the south and southeast of the Toroparu deposit, and the Ameeba Hills anomalies. Work in the Otomung area resulted in weak findings, possibly due to masking of the saprolite by overlying clay layers several metres thick. None of the exploration samples described in this section have been used for the current mineral resource estimate.

Regional and local mapping has been undertaken in phases since 1950, both by the title holders and by external parties, including the GGMC. The GGMC undertook regional mapping supported by geochemical drainage sampling in 2000, which showed gold and copper anomalies in the immediate Toroparu area.

ETK began auger drill sampling in 1999 to the east and west of the Toroparu deposit saprolite pit to evaluate re-processing the tailings from previous mining. Further auger drilling was carried out between 2001 and 2003 in the same area. In 2008 mechanized auger drilling was conducted over a 2 by 3 km area to the northwest of the Toroparu saprolite open pit. Nine northeast trending lines of auger samples were collected, spaced 500 m apart, to test the saprolitic rocks beneath the alluvial cover in an area of historic gold workings. In 2009 approximately 2,500 saprolite samples were collected from hand and power augers from depths of 1 to 15 m. The sample grids were oriented perpendicular to regional structures, extending approximately 4.5 km to the west-northwest of the Toroparu resource area, and identified several gold anomalies along the geological trends. In 2012, Sandspring collected 3,480 regional saprolite samples using a hand auger. Between 2013 and 2018, Sandspring conducted auger sampling to follow up on targets identified by regional structure and geology trends, and past and present alluvial gold prospecting.

Drainage geochemical sampling was conducted by the GGMC between 2003 and 2004 in the PL blocks to the north of the Toroparu saprolite pit and around the pit and reported that gold mineralization could extend at least 6 km to the northwest and 1 km to the southeast of the Toroparu saprolite pit. In 2011 Sandspring conducted a regional saprolite geochemistry sampling campaign in the Upper Puruni area, focussing on areas considered to be prospective for gold, including the surrounding northwest, north, and northeast areas of Toroparu, including the Ameeba, Manx, and Timmermans alluvial prospects. 2,891 samples were collected. Semi-regional and detailed geochemical sampling was performed on areas where alluvial mining activities showed gold potential, for a total of 4,390 samples. Additional work by Sandspring was completed in 2012, which increased the samples to a total of 7,850 covering an area of around 450 square km. In 2013 Sandspring collected 378 saprolite samples from the Makapa area over a grid of 200 by 100 m, which confirmed a north-northeast oriented, 1 km long and 500 m wide gold anomaly covering two small hills. At Sona Hill, Sandspring conducted concurrent geochemical sampling and geophysical surveys during 2015 and 2016 on a 100 by 50 m grid, but there were very few exposed alluvial sediments.

Geochemical samples collected during 2010 and 2011 were taken from the soil layer, and if possible, from the laterite layer, at a depth of approximately 0.3 and 0.5 m, using a hand auger. QAQC samples comprising blanks, standards, and field duplicates were submitted for every 20 routine sample intervals. The samples were dried and prepared at the onsite Acme preparation laboratory and assayed using inductively coupled plasma (ICP) analysis.

Geochemical samples collected during 2015, 2016, 2017, and 2018 were submitted to Bureau Veritas Commodities Laboratory (Bureau Veritas) for assay by aqua regia digestion and ultratrace ICP analysis.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Trench channel samples were completed by ETK in 2005 and 2006 to investigate gold mineralization in the saprolites of the pit area over an area of about 180 by 100 m. In 2009, ETK completed 41 trenches totalling 6,000 m, spaced at regular intervals and oriented perpendicular to the regional structural trend, over a 5 km strike length to the northwest of the Toroparu saprolite open pit.

In 2006 and 2007, TerraQuest conducted a 5 by 4.5 km high resolution tri-sensor magnetic and radiometric airborne survey for ETK around the Toroparu saprolite open pit area. This work identified a magnetic low area just to the north of a large magnetic high area of unknown origin. The survey outlined a number of magnetic and radiometric anomalies in the areas adjacent to the Toroparu saprolite open pit.

In 2010, 85-line kilometres of gradient array induced polarization and magnetometer surveys were performed by Insight Geophysics for Sandspring over the Toroparu deposit area and at the Ameeba, Manx, and Timmermans prospects. The surveys were done along 200 m spaced lines over an area of 4.8 by 2.8 km. The induced polarization surveys showed anomalies corresponding to the Toroparu granodiorite pluton. Chargeability was low over areas of high gold-copper mineralization despite the presence of sulfides. In 2011, 17 line kilometres of combined gradient array induced polarization and magnetometer surveys were carried out at Ameeba, Timmermans, Manx, and northwest of the Toroparu deposit, to complete the grids begun in 2010. At Sona Hill, Sandspring conducted an 18-line km induced polarization survey in 2015 to 2016 over the saprolite geochemical sampling grid, which suggested an extension of the west dipping, low angle, strongly altered shear zone to the west, with the potential for additional mineralization in the hangingwall. The chargeability survey did not reveal any significant results due to the low sulfide content of the Sona Hill mineralization. Resistivity did not provide reliable information to differentiate lithology, due to the similar mineralogy of the intrusives and volcanics.

In 2011, Sandspring flew a LIDAR survey over a 250 square km area around the Toroparu deposit to produce a detailed topographic contour map.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Drilling has taken place at the Property from 2006 to 2022, mostly for resource definition at the Toroparu and Sona Hill deposits, and for exploration at the Wynamu, Ameeba, Red Dragon, Majuba, and Timmermans prospects. A total of 1,326 drillholes for 265,948 m are present in the Project drilling database. A drill summary table is provided in Table 10-1.

Additionally, 13 geotechnical and 110 condemnation drillholes were drilled between 2021 and 2022.

The drillholes in the Toroparu and Sona Hill deposits have adequate spacing between holes to define mineral resources for the mineralization style. Some of the drillholes at the periphery of the deposits or with a wider drilling grid have not been considered for the mineral resources estimate. Drilling considered for the mineral resource estimate corresponds to 617 diamond drill holes at Toroparu and 152 diamond and 29 reverse circulation holes at Sona Hill. Both deposits are open at depth.

As the drillhole intersections through the mineralized zones are used as an input into the mineral resource estimate, the relevancy of the raw drillhole sample assay results are superseded by the mineral resource estimate and are more meaningfully described in the context of the mineral resource estimate.

A plan of the drillhole collars is provided in Figure 10-1 (source: Aris Mining, 2025) and a representative cross section of the drillhole spacing with the lithological and weathering model is provided in Figure 10-2 (source: Aris Mining, 2025), with a view to the northwest.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

All drilling at the Project has been undertaken on behalf of the Property owners by Orbit Garant Drilling Services (Orbit) of Canada.

Drillholes were initially collared in the field using a mobile handheld GPS. Downhole surveying was carried out by Orbit using a digital EZ Track single/multi-shot instrument at 50 m intervals. The first downhole survey measurement was conducted at 15 m down the drillhole and compared with the initial surface compass measurement. On completion of the drillholes, the drillhole collars were marked in the field with steel pipe or steel bar monuments marked with the drillhole identification numbers. Finally, all the drillhole collars were accurately surveyed by differential GPS and validated against the LIDAR topography.

All diamond drilling was undertaken using triple tube initiated at HQ diameter (77 mm) and completed through the first 30 to 40 m of saprolite into hard rock, then reduced to NQ diameter (60 mm) for the remainder of the drillhole.

Core was produced in 3 m core runs and to a lesser extent 1.5 m and placed into core boxes. Blocks were placed at the end of each drill run by the driller to record hole depths. Core was marked and oriented to check against the driller’s depth blocks, ensuring that all core loss was considered. Core recoveries were recorded at the drill site by drill run. The core boxes were then transported by the field technician to the core logging facility.

The core was cleaned and checked for continuity, and downhole depths were marked. The geologist completed geological logging for all drillholes, including lithology, alteration, structural characteristics and rock quality designation, and recorded in a digital format following standard procedures and geological codes. Data was recorded onto software to manage the geology database with a customized lithology, alteration, and mineralization code library.

All core, where possible, was oriented by field technicians at the drill rig using an ACT III NQ3 orientation tool in unweathered rock, usually from 50 m downhole. The oriented parts of the core were pieced together, an orientation line was drawn on all core pieces, and the structural data was recorded onto Reflex IQ-Logger.

Structural measurements included the orientation of fractures, lithology contacts, foliation, and veins/veinlets, and alpha and beta angles of structural features were recorded from oriented core. In situ quartz vein and other structural orientations were also obtained from 45 drillholes at Sona Hill in 2016.

In 2012 nine drillholes were surveyed by Terratec-Geoservices, measuring optical image, ultrasonic image, natural gamma ray emissions, electrical resistivity, induced polarization, azimuth and dip, and total magnetic field, and provided an interpretation of the images identifying the fractures-foliation contacts and veins.

In 2014 Sandspring carried out a relogging campaign to maintain the consistency of the logging of the different drilling campaigns, which has been maintained to date.

All cores were photographed both wet and dry prior to sampling.

Average core recoveries of 93% were achieved. Minor instances of low recovery were recorded, typically within the first 10 m of drilling related to the saprolite zone.

There are no details available regarding the reverse circulation drilling procedure, although they are likely to have been completed using industry standard methods. These holes are mostly located in non-mineralized or very low grade zones and have minimal impact on the mineral resource estimates.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Condemnation drilling is recommended in the area of planned Project infrastructure to ensure that no potentially economic mineralization underlies the proposed infrastructure. A first pass 400 by 400 m grid is recommended in the areas of the tailings facility, camp area, airstrip, processing plant, and waste dumps. The program will comprise approximately 100 drillholes for 6,000 m, for an estimated cost of $1.5 million.

There are no known drilling, sampling, or recovery factors that could materially impact the accuracy and reliability of the results, and the data is considered suitable for the estimation of mineral resources.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The sample preparation methods, quality control, security, and chain of custody measures were maintained over the drilling periods with some slight changes as a result of continuous improvement. Sample preparation, assaying and analytical procedures were carried out by MS Analytical (MSA), Acme Analytical Laboratories (Chile) S.A. (Acme, now Bureau Veritas), and Actlabs Guyana Inc. (ACT). Approximately 71% of the samples used in the mineral resource estimate were analyzed by Acme, 16% by MSA, and 8% by Acme. Acme was the main laboratory for Sona Hill.

The sample intervals were marked by the geologist and the core was cut in half with a diamond bladed saw. Saprolite samples were split with a trowel. Both the diamond bladed saw and trowel were cleaned before each sample. The majority of sample lengths are 1.5 m, with a minimum length of 0.5 m respecting lithological contacts. There are unmineralized narrow dykes less than 0.5 m, and in this case the sample was proportionally completed with wall rock up to 0.50 m.

The sampled half of the core was placed in a labelled bag with a tag number, and the remaining half of the core was retained as reference core kept in the core boxes and photographed.

All on-site sampling was conducted by company employees who managed the security and chain of custody throughout the receipt of the core at the drill rig, the logging, sampling, and delivery to the laboratory.

Between June 1, 2011, to 2014, sample preparation was completed at the on-site facility managed and operated directly by Acme. The prepared samples were then flown to Acme Laboratories in Georgetown and from there shipped to either Acme of Santiago, Chile, or Vancouver, Canada, for analysis.

Before Acme was acquired by Bureau Veritas, it was accredited under the ISO 9001:2000. Most of the sample were prepared on-site by Acme and analyzed at their facility in Chile. Acme is ISO 9001:2008 and ISO/IEC 17025:2005 certified, and sample preparation and analyses were done at their facility in Canada.

The samples sent to the MSA Laboratory were prepared and analyzed at their Georgetown facility. MSA has ISO 45001:2018 and ISO 9001 certifications, and ISO 17025 accreditation.

There are no records of accreditation for ACT. All the samples analyzed by ACT were prepared and analyzed at their Georgetown facility.

Acme, MSA and ACT operate as independent commercial certified laboratories both locally and internationally and have no relationship with the past or present Project operators.

Sample preparation at Acme involved initial weighing and drying each sample. The entire sample was then crushed to 80% passing -10 mesh and a 250 gram split was taken and pulverized to 85% passing -200 mesh.

At MSA, the entire sample was dried and crushed to 70% passing -10 mesh. A 250 gram sample split was taken for each sample and pulverized to 85% passing -200 mesh.

There are no records of the sample preparation method used at the ACT facility.

All samples were assayed for gold using fire assay on a 50 gram charge with atomic absorption spectrometry (AAS) finish. Any sample with an assay greater than 10 g/t Au was re-analyzed using fire assay with gravimetric finish. Most of the Toroparu samples were assayed for copper while at Sona Hill, copper analysis was performed selectively, given the low copper content at the deposit. Samples were not regularly assayed for silver. For copper and silver, the samples were analyzed by four acid digest with AAS finish on a 0.5 gram charge.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

In 2014, a campaign was initiated to assay existing sample pulps, by compositing two existing typically 1.5 m intervals into one 3.0 m interval. These samples were assayed mainly using aqua regia digestion of a 15 gram split, with an ICP finish.

In 2016, 973 pulp samples were assayed by Acme for cyanide soluble copper for metallurgical processing and mine planning. The data was insufficiently representative for the intended purpose and the work was abandoned.

Sandspring initiated a QAQC protocol in 2010 that included the submission of one coarse duplicate, two certified standards, and a blank sample for each 32 regular samples. Monthly QAQC reports of assay results were subject to a pass/fail process where QAQC data were evaluated against set parameters and were either passed or failed. When the QAQC sample failed the evaluation, a corrective action was taken which sometimes included re-assay of the entire batch. Re-assays were subject to the same evaluation process.

QAQC data submitted with drill samples from Toroparu prior to 2020 included 4,220 submissions from a pool of 14 different certified standards, 2,784 coarse blanks, and 1,252 core duplicates. Ninety-two sample swaps or laboratory failures were identified in the results returned for the certified standards. The blank results indicate possible short-term calibration issues at the laboratory, but no significant grade contamination is evident. No issues were identified with the duplicate sample results.

During the 2020 to 2021 drilling campaigns at Toroparu, QAQC data submissions included 622 samples from a pool of five different certified standards and 854 coarse blanks. No issues were identified with the standard results, and no significant grade contamination is evident.

Drill samples from the Sona Hill deposit submitted during 2012 and 2017 to 2018 included 421 submissions from a pool of six different certified standards, 216 coarse blanks, and 257 core duplicate samples. No issues were identified with the standards, blank samples, and the duplicate samples.

Bulk density measurements were completed on 0.1 m lengths of core, at 15 and 25 m depths downhole, and subsequently every 25 m in saprolite. In bedrock the measurement was taken at every 50 m intervals. All measurements were completed onsite by company employees, using the weight in air, weight in water method. In the saprolite zone the core was covered with plastic to seal the pores before measuring the wet weight. The paraffin wax sealing method was not used as the core was mostly in unweathered rock and has little or no porosity.

It is the opinion of the Qualified Person that the sampling, sample preparation and analysis, security, and QAQC protocols are consistent with generally accepted industry best practices and are suitable for the mineral resource estimate. The Qualified Person’s review of the QAQC data has shown that there is no indication of any material bias in the assays, there is no evidence of material sample contamination, and the duplicate samples show the expected variability for the mineralization style.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The qualified person responsible for geology verified the geological data supporting the mineral resource estimate through the personal inspections and through collaboration with the Project team, including:

In the opinion of the qualified person, the data used for the purpose of estimating the mineral resources are sufficiently reliable.

The qualified person responsible for metallurgy verified the metallurgical and processing factors supporting the mineral resource estimate and the results of the PEA through collaboration with the Project team. The metallurgical testwork reports supports:

It is noted that all testwork was conducted by accredited laboratories, and that in the opinion of the qualified person, the testwork meets best industry practices and the results indicate no evidence of significant bias that could adversely impact the developed process plan. In the opinion of the qualified person, the assumptions used for the purpose of estimating the mineral resources, the processing and production schedule, and the results of the PEA are sufficiently reliable.

The qualified person verified the mining factors supporting the mineral resource estimate, the optimized and designed pits, and the results of the PEA through the personal inspection and collaboration with the Project team, including reviews of:

In the opinion of the qualified person, the data used to support the mineral resource estimate and the results of the PEA are adequate and suitable for that purpose.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Numerous metallurgical testwork programs starting in 2009 have been undertaken to characterize the feed grade mineralization of the Toroparu and Sona Hill deposits, including both oxidized saprolite and sulphide fresh rock, and the material’s response to comminution, gravity concentration, rougher and cleaner flotation, and cyanide leaching. The testwork utilized samples that were representative of the growing mineral resource as it was known at the time of the studies. These studies included processing method trade off studies as well as refinements of the selected operating parameters, as the properties and response of the samples under the testwork conditions were increasingly better understood.

Beginning in 2012, testwork was undertaken on average and low copper grade composites to support the proposal that two geographically distinct types of gold mineralization distinguishable by sulphide and copper content could be mined, stockpiled, and processed separately to improve processing efficiency and overall recovery. As this geographic distinction is not currently demonstrated by the drillhole assays, the proposed separation of average and low grade copper mineralization has not been considered in the current PEA.

The following is a summary of the relevant testwork programs and results for samples representative of the material included in the economic analysis that have been utilized for the current assumptions in this technical report.

Testwork programs were undertaken by SGS on core samples from Toroparu in 2009, 2011, 2012, and 2013, by Inspectorate in 2012 and 2013, FLSmidth in 2014, and by ALS in 2015. Testwork programs were undertaken on core samples from Sona Hill by Base Metallurgical Laboratories in 2019, 2020, and 2022. These testwork programs supported PEAs completed in 2011, 2012, 2019, and 2021, and a preliminary feasibility study in 2013.

The metallurgical database includes samples from 310 drillholes at Toroparu and 61 drillholes at Sona Hill, representing a range of lithologies, weathering types, and grades. 273 of these samples are located within the pit design at Toroparu and 56 are located within the Sona Hill pit design. The spatial representativity of the samples is good, as shown in the plans and long sections in Figure 13-1.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

A mineralogical assessment of the master composite used in the SGS 2011 testwork showed that the sample was dominated by silicates and with chalcopyrite the predominant sulphide mineral.

Gold deportment studies at a P80 of 150 microns showed that the majority of the gold (85.6%) was present as native gold, indicating that gravity recovery should be considered in the process flowsheet. Other gold minerals included electrum, maldonite, petzite, and hessite.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Liberation studies showed that the liberation of copper minerals improves substantially at grinds finer than 150 microns. In contrast pyrite is widely distributed with significant liberation in the range of 80 to over 90% at all size fractions. Copper minerals and pyrite have negligible mutual association, so producing a marketable concentrate was expected to be possible.

Semi autogenous grinding (SAG) mill comminution test results from SGS in 2011 on samples from the Toroparu main pit showed an average JK drop weight test A x b value of 23.3 and drop weight index (Dwi) value of 11.8, indicating that the feed material is in the hard category relative to values in the JK Tech Dwi database. The Bond ball mill work index (Bwi) was 18.2 kWh/t and the Bond rod mill work index (Rwi) was 19.3 kWh/t, which confirmed the hardness. The Bond abrasion index (Ai) was reported as 0.294 g, within the abrasive range.

Testwork by Base Metallurgical Laboratories in 2022 tested a series of variability samples from the northwest and southeast pits. The Bwi test results from the southeast zone averaged 15.8 kWh/t, indicating a moderate to hard feed material, and the northwest samples averaged 18.3 kWh/t, indicating a hard feed material. Similarly, A x b averaged 28.5, which is considered competent. Abrasion testing averaged 0.23 g.

Testwork by Base Metallurgical Laboratories in 2019 on saprolite samples from Sona Hill returned a Bwi of 8.6 kWh/t and an Ai of 0.011, indicating the feed material to be very soft and not abrasive. Samples of granodiorite returned a Bwi of 12.3 kWh/t, an Rmi of 14.1 kWh/t, and an Ai of 0.186, which classified the sample as moderately hard and mildly abrasive.

SGS’s testwork in 2009 on the Toroparu samples resulted in an overall gold recovery in the flotation rougher concentrate and cyanidation of the flotation tailings of approximately 98%. Cyanidation of the saprolite gravity tailings showed that more than 95% of the gold was extracted using conventional cyanidation conditions with low cyanide consumption. Further testing by SGS in 2011 indicated that gravity recovery of gold in the range of 30 to 50% could be possible at a primary grind size of 150 microns.

Flotation testwork was undertaken to test different flowsheets and grind sizes. This work showed that with standard flotation chemicals, rougher recovery was sensitive to grind size. The flotation of gravity tails showed that 120 to 150 microns would be a suitable primary grind size for the rougher flotation stage and that gold and copper were effectively recovered at mass recoveries in the range of 5 to 11%. In an alternative flowsheet, flotation of the residual copper minerals led to copper rougher concentrate recoveries ranging from 60 to 80%. A gravity tail flotation flowsheet with three open circuit rougher-cleaner tests found that 150 microns was the optimal grind size for recovery while maintaining a good mass pull for the cleaner circuits. The best recoveries of 83.3% copper, 76.1% gold, and 52.8% silver were obtained in the 150 micron grind size.

Cyanidation testwork conducted by SGS in 2011 was undertaken on the whole ore at a P80 target of 150 and 75 microns, as well as on rougher concentrate with 90% gold extractions on whole ore and 97% on the rougher concentrate. Regrinding led to increased leaching of copper in the rougher concentrate cyanidation. Cyanidation testwork was also completed on gravity tailings, rougher tailings, rougher concentrate, and Mozley gravity concentrate. This work concluded that direct cyanidation of the gravity tailing considerably improved gold recovery by 8.5% while copper recovery was improved through rougher flotation. Cyanide leaching was performed on gravity tailings at a range of grind sizes, as well as cyanidation of cleaner concentrate and tailings. The cyanidation of the cleaner tailing was excellent with a gold extraction of 88.2% while cyanidation of the cleaner concentrate was poor with a gold extraction of 59.0%. A cyanidation test on the cleaner scavenger tailings resulted in a final gold extraction of about 81%.

Later testwork by SGS in 2012 to 2013 was undertaken on average and low copper grade composites. The testwork of the average grade copper composites included gravity separation, flotation, and cyanidation of the flotation and gravity separation products, and the low grade copper composite testwork included gravity separation, rougher flotation, and

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

cyanidation of the gravity separation concentrate. The objective of this program was to compare the performance of direct cyanide leaching of the gravity tailing and cyanide leaching of a flotation product.

Gravity separation tests on the average copper grade material showed that gold recovery increased with reduction in P80 and was consistent over 150 microns, consistent with the 2011 test results, which indicate gravity gold recoveries in the range of 30 to 50%. Bulk rougher flotation was performed on the gravity tailings products for evaluation of grind size, and a P80 of 150 microns was selected for subsequent flotation testwork. Open circuit cleaning flotation tests showed that regrind had little to no effect on the performance of the cleaner flotation, and that the dosage of non-sulphide gangue depressant was critical. The response of the gravity concentrate, gravity tailings, and cleaner scavenger tailings streams to cyanide leaching was examined in a series of tests. Intensive cyanidation of the gravity concentrate resulted in gold extraction of 99% and 97% for silver. The results showed that the feed size had no effect on leaching recovery. Bulk cyanidation of the gravity tailings showed an increase in gold extraction with decreasing feed size while copper extractions were low and not influenced by feed size. Cyanide leaching of the gravity separation tailing offered higher gold and silver recovery than rougher flotation and also cleaner flotation combined with leaching of the cleaner tailing, however the cyanide consumption was much lower and copper extraction was much higher from the cleaner flotation processing route compared to the gravity tailing leaching route.

Gravity concentrate gold recovery for the low copper grade material ranged from 28.9% at a P80 grind size of 225 microns to 58.9% for a P80 grind size of 75 microns. Scoping rougher flotation tests were performed on gravity tailings produced at three different grind sizes, which showed that the recovery of copper and gold increased as a function of finer grind size, while the recovery of silver did not display the trend. The overall combined gravity and flotation gold recovery of all samples was 91.9%. Rougher concentrate obtained from the flotation tests were submitted for carbon in pulp cyanidation tests, which showed that gold extraction from combined gravity separation, rougher flotation, and rougher concentrate leaching ranged from 89 to 95%, silver extraction ranged from 60 to 82%, and copper did not exceed 14%.

The results showed that gravity separation and leaching of the gravity separation tailing for all grind sizes offered higher overall gold recovery. However, the cyanide consumption and capital cost of the direct leaching are essential factors in choosing the optimized method for gold recovery, as elevated dissolved copper levels in the loaded solution require additional treatment downstream. The results showed that cyanide consumption and copper extraction for the case of cyanide leaching of the cleaner tailing for the average copper grade composite was considerably lower than the direct cyanide leaching of the gravity separation tailing case. Conversely, in the case of the low copper grade composites, the cyanide consumption and copper extraction of the rougher concentrate was higher than the direct gravity tailing case.

Testwork by Inspectorate in 2012 and 2013 focussed on gold recovery from saprolites. The saprolite samples were subjected to gravity concentration using a 3 inch Knelson concentrator followed by Mozley table. Gold recoveries were 50% for the fine samples and 27% for the coarse samples. Intensive cyanide leaching of the gravity concentrates resulted in recoveries of 97% from both samples. Flotation tests on the fine saprolite sample were performed to investigate different P80 and reagent schemes on the recovery of gold, with the resulting recoveries ranging between 70 to 86.7%. Cyanide and carbon in leach tests showed that varying sodium cyanide dosages had no effect on gold recovery, and the carbon in leach tests achieved slightly higher recoveries than cyanide leach.

Flotation tests were conducted by FLSmidth in 2014 on average copper grade samples at a target grind size of 150 microns to evaluate the use of copper selective collectors to produce a high copper grade rougher concentrate followed by a bulk rougher scavenger float to maximize recovery. Extended rougher scavenger flotation reached overall flotation recovery of approximately 97% copper, 86% gold, 78% silver, and 98% total sulphur. Leach tests were also conducted to evaluate the impact of grind size on overall gold recovery, which showed that gravity gold appeared to peak at around 120 microns in the low copper grade composites, while both leach and overall recovery steadily improved with finer grind. Diagnostic leach tests were used to determine the association of the unrecovered gold from these tests, which showed that more of the unrecovered gold was found to be cyanide extractable at grind sizes finer than P80 of 159 microns. Testwork was also conducted on saprolite samples which showed that overall, approximately 99% of the gold was recovered from each of the bulk composites with between 29 and 52% of the gold recovered in the gravity circuit and the remainder recovered through the cyanide leach. Overall gold recovery from the sub composites ranged from approximately 93 to 99% with gravity recovery ranging from 5 to 38% and cyanide extractions accounting for a further 61 to 88%.

A series of batch rougher and cleaner tests and regrind tests were conducted by ALS in 2014 to develop a flowsheet and reagent scheme for copper recovery. A gravity stage on the flotation flowsheet was not found to increase the overall gold

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

or silver recovery; however, it was considered that the revenue from gold from a gravity concentrate would probably be greater than the losses attributed to the gold sales from a mixed concentrate. The optimal test results in terms of copper performance utilized potassium amyl xanthate (PAX) and a split regrind configuration.

Testwork by Base Metallurgical Laboratories in 2022 on variability samples from the northwest zone was conducted via a gravity leach flowsheet, with half of the 18 samples returning recoveries lower than 85%. Samples from the southeast zone under the same flowsheet were much better with an average recovery of 92.1%. Gravity rougher tests on the northwest samples showed an 82% gold recovery and an 83% copper recovery. Poor copper recoveries were linked to low sulphur levels. The southeast zone had an average gold recovery of 85.5% and an average copper recovery of 84.4%. The poor performing samples also had a low sulphur content. Gravity leach and gravity rougher underwent three stage diagnostic leach tests which showed the majority of gold as cyanide leachable, and copper consistently locked in acid digestible minerals with minor cyanide leachable components.

Testwork by Base Metallurgical Laboratories in 2019 followed flowsheets including a primary grinding stage followed by Knelson gravity concentration and cyanide leaching of the gravity tailings. The flowsheets evaluated implemented a rougher flotation stage prior to leaching the gravity tailings, as well as cyanide leaching of the rougher concentrate with and without a regrind stage. The testwork further investigated the effect of cyanide leaching with gravity concentrate, with and without a regrind stage. The test results with a gravity leach flowsheet showed high extractions of 94 to 98% from the saprolite sample, 81 to 85% for the granodiorite sample, and between 74 and 85% for the high quartz granodiorite. Finer primary grinding of the samples resulted in a minor improvement in leach kinetics and gold extraction. At a primary grind size of P80 53 microns, testwork showed a significant increase to gold extraction and leach kinetics of the gravity tailings at a pH of 12.5. Implementing a rougher flotation stage after the gravity concentration and regrinding the rougher concentrate prior to leaching resulted in a significant increase in overall gold recovery of up to 96% for the granodiorite sample and up to 97% for the high quartz granodiorite.

Leach residues were subjected to a multi-stage diagnostic leach test to determine the gold deportment in the leach residues, and the results indicated that the majority of the gold may be associated with arsenical minerals or minerals that are attacked by nitric acid. However, it was considered most likely that the association with tellurides was responsible for the bulk of the residual gold.

Trace mineral search in rougher concentrates showed that gold occurred mainly as minerals containing tellurium and locked binaries with pyrite and sulphide gangue, so further regrinding would be necessary to expose the gold surface for cyanide leaching, and extended times may be required as tellurium minerals are slower in leaching. Further testing explored the effect of fine grind and high pH leaching on tellurium samples, which showed some grind sensitivity to leach extraction at a pH of 10. However, the benefit was observed to be limited and potentially not economic to chase finer and finer grinds. Coarser grind sizes in the range of 106 to 125 microns at an elevated pH of 12.5 typically presented higher extractions than those achieved at finer grinds and low pH.

Testwork by Base Metallurgical Laboratories in 2020 blending Sona Hill and Toroparu samples showed high extractions under the elevated pH conditions with mid to high 80% and low 90% extractions. The work suggested that there is some synergistic benefit in blending the material types with the potential that the lower pH saprolite is partially neutralized by the other samples. Leaching was observed to be substantially complete at 48 hours and several percent points of additional leach extraction were achieved over the 24 to 48 hour period.

Continuous SO2/air cyanide detoxification tests were undertaken in 2014 by ALS on a master cyanidation tailings composite. The weak acid dissociable (WAD) cyanide target for the treated effluent was less than 5 mg per litre. The key findings of the testwork were that the material is amenable to the SO2/air process and that the target was achieved.

The combined metallurgical recoveries for sulphide material are estimated at 93% for gold, 78% for silver, and 88% for copper. For oxide material the combined metallurgical recoveries are estimated at 97% for gold and 46% for silver. Overall, recoveries are estimated at 93.6% for gold, 77.0% for silver, and 86.1% for copper.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

Copper concentrate analyses were undertaken by ALS in 2014 to identify deleterious elements that may invoke penalty upon sale, identifying bismuth (380 to 631 g/t), selenium (500 to 770 g/t), and tellurium (292 to 396 g/t). Arsenic content was close to typical penalty thresholds. Further metallurgical testwork is required to better define potential concentrate quality, and therefore no penalties have been included in the current economic analysis.

The metallurgical testwork to date has been conducted on a wide range of samples representative of the material expected to be processed in the life of mine plan. The studies have been conducted to a sufficient quality and extent to support the process flow sheet, cost estimates, and economic analyses presented in this PEA.

There are no known processing factors or deleterious elements that could have a significant effect on the economic extraction of the mill feed that have not been considered and accounted for in the processing plan and economic model.

No fatal or significant flaws were detected during the review of the testwork and the current proposed flowsheet. The level of testwork conducted to date that supports the development of a process design criteria document that has resulted in a flowsheet that recovers the required amount of gold, silver, and copper at saleable grades and meets the typical expectation for a PEA level of study.

The Project metallurgical testwork has confirmed that flotation and free milling cyanidation process routes are capable of achieving higher recoveries of both gold and copper as well as payable silver values.

Processing saprolitic material will add viscosity considerations, and the softness will reduce the power demand in the milling circuit. High saprolite blends may allow elevated processing rates of hard material.

Soluble cyanide copper will need to be managed for the Toroparu mill feed. The impact of copper on the carbon circuit should be evaluated at a range of soluble copper concentrations.

Mineral analysis on the copper concentrates produced from the Toroparu deposit identified deleterious elements that may have some penalty on concentrates, including bismuth, selenium, tellurium, and arsenic.

Auriferous tellurides from Sona Hill material are slower leaching and require a finer grind and elevated pH to achieve high extractions. Blending Sona Hill material with Toroparu material will increase the operating cost of the Toroparu material, which will be managed in the processing schedule. Telluride leach kinetics should be tested in future studies. The high pH regimes required to process the Sona Hill material will influence the carbon circuit performance, which should be considered in the design of the elution technology and the process selection. It is also a consideration for the cyanide detoxification process and the design and capacity of reagent systems, notably the pH modifier.

The key assumptions utilized for the development of the current proposed flow sheet are shown in Table 13-1.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The current PEA is based on testwork conducted over the past decade using similar, but not identical, samples and objectives. To progress the Project to a Preliminary Feasibility Study level, a comprehensive metallurgical testwork program is recommended to confirm the chosen process criteria for both oxide and sulphide mill feed. The focus of this work should be on the Toroparu deposit, with all testwork performed on representative samples from within the mining schedule to ensure a reliable PFS level design can be further developed.

The recommended studies and testwork include:

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The cost to complete this testwork and the PFS is estimated at $1.25 million.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The current mineral resource estimate for the Project was prepared under the supervision of or was reviewed by Pamela De Mark, P. Geo., Senior Vice President of Geology and Exploration of Aris Mining. The mineral resource estimate has been prepared in compliance with the CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines of 2019 (CIM, 2019) and reported in compliance with the CIM Definition Standards for Mineral Resources and Mineral Reserves of 2014 (CIM, 2014). The mineral resource estimate utilizes a cut-off grade calculation with an effective date of October 21, 2025.

There are no known environmental, permitting, legal, title, taxation, socio-economic, marketing, political, or other relevant factors that could materially affect the mineral resource estimate.

The data available for the mineral resource estimate is shown in Table 10-1. A total of 1,077 drillholes was used for the geological interpretation for the Toroparu deposit and a total of 212 drillholes was used for the Sona Hill deposit. Data validation was conducted including ensuring all drillholes have all of the appropriate logging information, final assay and logging depths match the end of hole depth in the drill collar table, checks for overlapping or gaps in the assay and logging tables, checks for duplicate drillhole names and duplicate coordinates, checks for null data, checks for integer survey values indicating a lack of detailed survey data, and checks for extreme variations in drillhole azimuth or dip between consecutive downhole survey records. A number of errors, including poorly oriented holes, were identified and managed by removing that data from the database used for the mineral resource estimate.

The drillhole geological logging data and sample assays, supplemented with core photographs, regional aeromagnetic data, and mapping were used to create wireframe interpretations of weathering and lithology. The weathering and lithology codes were grouped based on recommendations from Pratt and Smeraglia (2022). The weathering codes include transported/overburden, oxide/saprolite, transitional, and fresh zones. The lithology codes include dykes, gabbro, intrusives, volcanics, undifferentiated volcanics, and sediments. A plan of the interpretations is shown in Figure 7-4 (source: Aris Mining, 2025).

The Project mineralization exhibits anastomosing, sigmoidal patterns in core and outcrop. These small-scale patterns were used to interpret the larger scale patterns for the mineralization domains used to estimate gold, copper, and silver grades. The mineralized veins have been folded, sheared, transposed and boudinaged at scales ranging from 0.1 m to a few metres. Mineralization interpretations, including zones of internal waste, were created for low and high grade gold domains at Toroparu and Sona Hill, and high grade copper at Toroparu. Silver grades were estimated from within the gold and copper domains. Plans of the gold and copper mineralization are shown in Figure 7-5 (source: Aris Mining, 2025).

The drillhole data was selected and coded with the lithological and mineralization interpretation wireframes, and then composited to a 1 m length. Top cuts were applied to the 1 m composites and additional restrictions were applied to values close to the 95th percentile of the population by using a high-grade restriction rule when estimating grades into the block model.

The statistics for gold, copper, and silver of the composited and top cut composited data are shown in Table 14-1.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

At the Toroparu deposit, two parent block sizes were utilized, including a size of 10 mE x 10 mN x 5 mRL where the average drillhole spacing is within 25 m and a 20 mE x 20 mN x 5 mRL parent block size for all other areas. A single block size of 12.5 mE x 25 mN x 10 m RL was used for Sona Hill. The geology and mineralization interpretation wireframes were used to code the block model for each of the features.

Bulk density measurements were taken from 7,067 samples from the Toroparu deposit and 723 samples from Sona Hill. The average bulk densities were applied to the block model as shown Table 14-2.

Variograms were completed on the composited data for each mineralized zone to characterize the spatial continuity of each element and validated with the mineralization interpretations to ensure that the correct orientation of strike, dip and plunge directions of the search ellipsoid created from the variograms were compatible with the mineralization or structural orientations.

Ordinary kriging was used to estimate gold, silver, and copper grades into the block model utilizing dynamic anisotropy to adjust the search orientations with changes in the strike and dip of the mineralization. Three searches were used at Toroparu, with the first search utilizing a minimum of five or eight and a maximum of 30 composites within the first 60% of the range of the element’s variogram. The second search used a minimum of four or eight and a maximum of 15 to 25 composites and extended to the full extent of the variogram. The third search was allowed to fill any other un-estimated blocks. Less than 10% of the blocks were estimated in the third search with a minimum of one and a maximum of 5 composites. At Sona Hill, a minimum of six and a maximum of 20 composites were used for the first and second searches. The third search used a minimum of two and a maximum of 20, and a fourth search used a minimum of two and a maximum of 10 composites. A maximum of five composites per drill hole was applied for all searches.

Standard block model grade estimation validation was completed using visual and numerical methods, including visually comparing estimated grades with input composite grades, the assessment of swath plots, and global statistical comparison of estimated grades with declustered composite grades. An example cross section of the Toroparu gold estimate compared to input composite grades is shown in Figure 14-1 (source: Aris Mining, 2025).

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The mineral resource has been classified as either measured, indicated, or inferred based on confidence in the geological interpretation, grade continuity, sample spacing, and volume constraint.

Measured classification was applied at Toroparu only where the drill grid spacing was less than 30 m along strike and 40 m down dip, estimated within the first search pass, and with a minimum of 90% of the blocks with a slope of regression greater than 0.4. Indicated was applied at Toroparu where the drill grid spacing was less than 60 m along strike and 80 m down dip, estimated within the second search pass, and with a minimum of 80% of the blocks with a slope of regression greater than 0.2. At Sona Hill, indicated was applied where the drill spacing was less than 40 m along strike and down dip, estimated within the first or second search, and with a kriging efficiency of greater than 50%. Inferred was applied at Toroparu where the drill grid spacing was less than 150 m along strike and down dip, and estimated within the third search pass. At Sona Hill, inferred was applied where the drill grid spacing was less than 100 m along strike and down dip and estimated within the second or third search pass. Strings were digitized on drill sections considering this criteria to construct volumes used to code the mineral resource category to the block model.

The mineral resource estimate has been tabulated using a cut-off grade of 0.45 g/t Au for open pit resources and 1.5 g/t Au for underground resources, based on the assumptions shown in Table 14-3. The optimized pits used for constraining the mineral resource estimate are shown in Figure 16-1.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

An optimized pit and optimized stopes were created to constrain the open pit and underground mineral resources using a gold price of $1,950 per ounce and gold cut-off grades of 0.45 g/t for open pit mineral resources and 1.5 g/t for underground mineral resources. The Toroparu mineral resource estimate effective October 21, 2025 is shown in Table 14-4.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

This section is not applicable to this technical report.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The Toroparu and Sona Hill deposits will be mined using conventional open pit mining methods. The operation will utilize conventional drill rigs, excavators, haul trucks, dozers, graders, water trucks, and utility vehicles.

Run of mine material from the Toroparu pits will be hauled from the pit benches to a dedicated run of mine stockpile located close to the Toroparu open pit area and processing plant. Run of mine material from the Sona Hill pit will be hauled approximately 8 km to the run of mine stockpile at the processing plant. Waste material will be hauled from the Toroparu and Sona Hill pits to their designated waste storage facilities located in close proximity around the two open pit areas. Topsoil will be stored separately for future rehabilitation requirements.

Material will typically be blasted in benches ranging from 10 to 20 m high, with 10 m benches assumed for the smaller equipment mining overburden and most saprolite, and 20 m benches for the larger equipment mining transition, sulphide rock, and selected areas of saprolite. Given the softness of the overburden and near surface saprolite, free digging and ripping opportunities will be considered where possible. Most of the overburden and approximately 75% of the saprolite is expected to be excavated without blasting.

The general mining related layout includes the Toroparu main, northwest, and southeast pits, the Sona Hill pit, a waste rock storage facility located to the northeast of the Toroparu pits, a waste rock storage facility located to the east of the Sona Hill pit, a low grade stockpile located to the west of the Toroparu northwest pit, a run of mine stockpile located at the processing plant, and haul roads. A plan of the general layout is shown in Figure 18-1.

The existing geotechnical work that has been considered for the pit design includes work undertaken by Knight Piésold in 2013, 2014, and 2018. The work included visual inspections, core logging and sampling, permeability testing, piezometer instrumentation and monitoring, laboratory rock/soil testing, and downhole televiewer surveys. The data collected allowed geotechnical models to be developed to assess pit slope stability to provide pit slope design parameters for benches, inter-ramp slopes, and the maximum overall pit slope angles that can be accommodated in each of the pit design sectors in the softer saprolite and harder underlying bedrock.

The recommended pit slope configurations are shown in Table 16-1.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The Project is drained by the Puruni and Wynamu rivers, the confluence of which was historically at the Toroparu southeast pit location, but has been altered by artisanal mining activities. The predominant flow direction is to the south-southeast over very flat surface topography. The rivers directly influence the proposed Project infrastructure, with all of the open pits located within the floodplain areas of the two rivers. The rivers will be diverted to allow for proper surface water management and to mitigate safety concerns associated with flood events by constructing stream diversion canals and levees. These rivers are the main receptors.

The mine site has very low relief with shallow groundwater levels. There are no villages or communities dependent on groundwater within the Project area, with the nearest village located at Puruni approximately 100 km away.

The mean annual precipitation is high at 2,130 mm based on statistical analysis of approximately 26 years of daily rainfall data. There are two drier periods and two periods of higher precipitation, with the first dry period from February to April, the main rainy season from May to August, a second dry period from September to October, and a secondary rainy season in November to January. The average annual rainfall exceeds 200 mm per month. The estimated annual evaporation is 1,500 mm per year. From a hydrological perspective it is expected that sustained baseflows and high soil moisture will be prevalent, with peak runoff and flood risk in May to August.

The Project area consists of a shallow weathered aquifer consisting mainly of saprolite ranging from 0 to 40 m in depth that is underlain by a higher permeable transition zone at a depth of 40 to 45 m, and then by less permeable bedrock that typically gets less permeable with depth.

Large scale faults and lineaments may act as preferential groundwater flow pathways with enhanced permeability and groundwater flow typically occurring along and parallel to the strike of the structures and adjacent fractured zones. Structures may also act as barriers to flow across their strike due to disturbance zones, commonly with clay gouge, that inhibits groundwater flow.

Groundwater level transducers monitoring groundwater level changes since June 2022 in 12 drillholes indicate that the groundwater levels are in quasi steady state with no significant change over time in the saprolite, transition, and bedrock zones. Groundwater levels range between 2.4 to 24.7 m below ground level, with an average groundwater level depth of 11.7 m.

Water quality data from 2024 indicates that both surface and groundwater total dissolved solids are very good. None of the groundwater samples exceeded IFC guidelines for mining effluent. Half of the surface water samples exceeded IFC limits for iron, a single cadmium and mercury exceedance were found, as well as two suspended solids exceedances.

Thirty nine in situ packer tests were conducted in 2010 to determine site specific information on the rock permeability with depth. The subsurface was divided into five geological and hydro-stratigraphic zones with the saprolite zone overlying the transition zone and the upper, lower, and deep bedrock. The test results indicated that the hydraulic conductivity generally decreases with depth with the notable exception being the transition zone between the saprolite and the bedrock. The packer testing results were used to develop and calibrate a three dimensional numerical model.

A calibrated three-dimensional numerical groundwater flow model simulated the regional and local groundwater system in its pre-mining and life of mine state. Rainwater runoff from the pits were superimposed on the simulated groundwater inflows for each pit to account for fissure and rainwater separately. The numerical model further informed on the potential groundwater flow directions, pore pressure, and hydrogeological impacts of the mining infrastructure on the groundwater regime over the life of mine. Conservative assumptions were made to ensure simulated impacts are larger than in the actual expected case.

Pore pressures are expected to be elevated on the weathered and bedrock contact as well as on the pit slopes during mining. Pore pressures must be monitored during mining to determine if the slope stability is sensitive to pore pressures, and if the stability is sensitive, the active dewatering/depressurization measures could be enhanced to reduce pore pressures.

NI 43-101 Technical Report Preliminary Economic Assessment for the Toroparu Project, Cuyuni-Mazaruni Region, Guyana

The main Toroparu pit is expected to experience the highest pit inflows from groundwater and rainwater over the life of mine with a maximum expected inflow rate of 39,606 cubic metres per day. The Toroparu northwest pit is expected to have the lowest inflow rate with a maximum expected inflow rate of 6,770 cubic metres per day. Surface water ingress will be mitigated using outer pit stormwater cutoff trenches and berms to capture and divert surface water runoff away from the pits and site infrastructure. In pit sump pumps and trenches will be used to manage in-pit water. Boreholes will be drilled to target any geological structures that could act as subsurface conduits of groundwater flow. Aquifer testing will be done to quantify the vertical hydraulic conductivity of the saprolite and used to update the numerical model.

Following mine development, the pits are expected to accumulate water as precipitation exceeds evaporation by approximately 600 mm per year with decanting expected. Post operational pit lake water quality should be evaluated in future studies but is not expected to be significantly degraded given the high annual precipitation rate and expected dynamic flowthrough relative to evaporation and stagnation.

The peak make up water demand for mining is 359,334 cubic metres per month and can be sourced from rainwater harvesting, abstracted from the Puruni and or the Wynamu rivers, as well as boreholes. Excess contact and mine water will be managed and treated if required before being discharged to the environment.

The potential for chemical mass migration from mine residue facilities and the impact on receptors was evaluated with specific reference to sulphate and arsenic that were used as tracer constituents for potential mass migration. There are no known groundwater users that can be influenced by mass migration and the only known receptors are the Wynamu and Puruni rivers. Cutoff and surface water diversion trenches and scavenger wells will limit the extent of mass migration to the rivers. A model was developed to evaluate the potential risks from chemical mass leach and transport potential via the surface water and groundwater pathways at the tailings management facility. From a hydrogeological contaminant transport risk perspective, the tailings facility does not require a synthetic liner.