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Exhibit 97

SIGMA LITHIUM CORPORATION

CLAWBACK POLICY

The Board of Directors (“Board”) of Sigma Lithium Corporation (the “Company”) has adopted this Policy in accordance with Nasdaq listing requirements.

A.Application of Policy

This Policy applies in the event of any restatement (“Restatement”) of the Company’s financial results due to its material non-compliance with financial reporting requirements under the securities laws.1 This Policy does not apply to restatements that are not caused by non-compliance with financial reporting requirements, such as, but not limited to, a retrospective: (1) application of a change in accounting principles; (2) revision to reportable segment information due to a change in the structure of the Company’s internal organization; (3) reclassification due to a discontinued operation; (4) application of a change in reporting entity, such as from a reorganization of entities under common control; (5) adjustment to provision amounts in connection with a prior business combination; and (6) revision for stock splits, reverse stock splits, dividends or other changes in capital structure (collectively the “Restatement Exclusions”).

B.Executive Officers Subject to the Policy

The “executive officers” of the Company are covered by this Policy. This includes the Company’s current or former Chief Executive Officer, Chief Financial Officer, any Vice-President of the Company in charge of a principal business unit, division or function, and any other current or former officer or person who performs a significant policy-making function for the Company, including executive officers of Company subsidiaries (the “Executive Officers”). All of these Executive Officers are subject to this Policy, even if an Executive Officer had no responsibility for the financial statement errors which required restatement.

C.Compensation Subject to the Policy

This Policy applies to any incentive-based compensation received by an Executive Officer during the period (the “Clawback Period”) consisting of any of the three fiscal completed years immediately preceding:

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This Policy covers all incentive-based compensation (including any cash or equity compensation) that is granted, earned or vested based wholly or in part upon the attainment of any “financial reporting measure”. Financial reporting measures are those that are determined and presented in accordance with the accounting principles used in preparing the Company’s financial statements and any measures derived wholly or in part from such financial information (including non-GAAP measures, stock price and total shareholder return). Incentive-based compensation is deemed “received” in the fiscal period during which the applicable financial reporting measure (as specified in the terms of the award) is attained, even if the payment or grant occurs after the end of that fiscal period.

Incentive-based compensation does not include base annual salary, compensation which is awarded based solely on service to the Company (e.g. a time-vested award, including time-vesting stock options or restricted share units), nor does it include compensation which is awarded based on subjective standards, strategic measures (e.g. completion of a merger) or operational measures (e.g. attainment of a certain market share).

D.Amount Required to be Repaid Pursuant to this Policy

The amount of incentive-based compensation that must be repaid (subject to the few limitations discussed below) is the amount of incentive-based compensation received by the Executive Officer that exceeds the amount of incentive-based compensation that otherwise would have been received had it been determined based on the Restatement (the “Recoverable Amount”). Applying this definition, after a Restatement, the Company will recalculate the applicable financial reporting measure and the Recoverable Amount in accordance with SEC and exchange rules. The Company will determine whether, based on that financial reporting measure as calculated relying on the original financial statements, an Executive Officer received a greater amount of incentive-based compensation than would have been received applying the recalculated financial measure. Where incentive-based compensation is based only in part on the achievement of a financial reporting measure performance goal, the Company will determine the portion of the original incentive-based compensation based on or derived from the financial reporting measure which was restated and will recalculate the affected portion based on the financial reporting measure as restated to determine the difference between the greater amount based on the original financial statements and the lesser amount that would have been received based on the Restatement. The Recoverable Amounts will be calculated on a pre-tax basis to ensure that the Company recovers the full amount of incentive-based compensation that was erroneously awarded.

In no event shall the Company be required to award Executive Officers an additional payment if the restated or accurate financial results would have resulted in a higher incentive compensation payment.

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If equity compensation is recoverable due to being granted to the Executive Officer (when the accounting results were the reason the equity compensation was granted) or vested by the Executive Officer (when the accounting results were the reason the equity compensation was vested), in each case in the Clawback Period, the Company will recover the excess portion of the equity award that would not have been granted or vested based on the Restatement, as follows:

The Board will take such action as it deems appropriate, in its sole and absolute discretion, reasonably promptly to recover the Recoverable Amount, unless all of the independent directors of the Board determine that it would be impracticable to recover such amount because (1) the direct costs of enforcing recovery would exceed the Recoverable Amount,2 or (2) recovery would likely cause an otherwise tax-qualified retirement plan, under which benefits are broadly available to employees of the Company, to fail to meet the requirements of 26 U.S.C. 401(a)(13) or 26 U.S.C. 411(a) and regulations thereunder3, or (3) if the recovery of the incentive-based compensation would violate the home-country laws of the Company.

E.Additional Clawback Required by Section 304 of the Sarbanes-Oxley Act of 2002

In addition to the provisions described above, if the Company is required to prepare an accounting restatement due to the material noncompliance of the Company, as a result of misconduct, with any financial reporting requirement under the securities laws, then, in accordance with Section 304 of the Sarbanes-Oxley Act of 2002, the Chief Executive Officer and Chief Financial Officer (at the time the financial document embodying such financial reporting requirement was originally issued) shall reimburse the Company for:

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issuance or filing with the Commission (whichever first occurs) of such financial document; and

F.Crediting of Recovery Amounts

To the extent that subsections A, B, C and D of this policy (the “Rule 10D-1 Clawback Requirements”) would provide for recovery of incentive-based compensation recoverable by the Company pursuant to Section 304 of the Sarbanes-Oxley Act, in accordance with subsection E of this policy (the “Sarbanes-Oxley Clawback Requirements”), and/or any other recovery obligations (including pursuant to employment agreements, or plan awards), the amount such Executive Officer has already reimbursed the Company shall be credited to the required recovery under the Rule 10D-1 Clawback Requirements. Recovery pursuant to the Rule 10D-1 Clawback Requirements does not preclude recovery under the Sarbanes-Oxley Clawback Requirements, to the extent any applicable amounts have not been reimbursed to the Company.

G.General Provisions

This Policy may be amended by the Board from time to time. Changes to this Policy will be communicated to all persons to whom this Policy applies.

The Company will not indemnify or provide insurance to cover any repayment of incentive-based compensation in accordance with this Policy.

The provisions of this Policy apply to the fullest extent of the law; provided however, to the extent that any provisions of this Policy are found to be unenforceable or invalid under any applicable law, such provision will be applied to the maximum extent permitted, and shall automatically be deemed amended in a manner consistent with its objectives to the extent necessary to conform to any limitations required under applicable law.

This Policy is in addition to (and not in lieu of) any right of repayment, forfeiture or right of offset against any Executive Officer that is required pursuant to any other statutory repayment requirement (regardless of whether implemented at any time prior to or following the adoption of this Policy). Nothing in this Policy in any way detracts from or limits any obligation that those subject to it have in law or pursuant to a management, employment, consulting or other agreement with the Company or any of its subsidiaries.

All determinations and decisions made by the Board (or any committee thereof) pursuant to the provisions of this Policy shall be final, conclusive and binding on the Company, its subsidiaries and the persons to whom this Policy applies. Executive Officers (as defined above) are required to acknowledge that they have read this Policy annually. If you have questions about the interpretation of this Policy, please contact the Chief Legal Officer of the Company.

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Exhibit 99.1

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INTERPRETATION

Definitions

For a description of defined terms and other reference information used in this Annual Information Form (this “AIF”), please refer to Schedule “B”.

CIM Definition Standards

The disclosure included in this AIF uses mineral resource and mineral reserve classification terms that comply with reporting standards in Canada. All mineral resource and mineral reserve estimates are made in accordance with the CIM Definition Standards and NI 43-101, which is a set of rules developed by the Canadian Securities Administrators that establishes standards for all public disclosure an issuer makes of scientific and technical information concerning mineral projects and operations. The following definitions are reproduced from the CIM Definition Standards:

A “mineral resource” is a concentration or occurrence of solid material of economic interest in or on the Earth’s crust in such form, grade or quality and quantity that there are reasonable prospects for eventual economic extraction. The location, quantity, grade or quality, continuity and other geological characteristics of a mineral resource are known, estimated or interpreted from specific geological evidence and knowledge, including sampling. Mineral resources are sub-divided, in order of increasing geological confidence, into inferred, indicated and measured categories, which are defined as follows:

“Modifying factors” are considerations used to convert mineral resources to mineral reserves. These include, but are not restricted to, mining, processing, metallurgical, infrastructure, economic, marketing, legal, environmental, social and governmental factors.

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A “mineral reserve” is the economically mineable part of a measured and/or indicated mineral resource. It includes diluting materials and allowances for losses which may occur when the material is mined or extracted and is defined by studies at pre-feasibility or feasibility level as appropriate that include application of modifying factors. Such studies demonstrate that, at the time of reporting, extraction could reasonably be justified. Mineral reserves are sub-divided, in order of increasing geological confidence, into probable and proven categories, which are defined as follows:

CAUTIONARY NOTE REGARDING FORWARD LOOKING INFORMATION

Certain information and statements in the MD&A included herein may constitute “forward-looking information” within the meaning of Canadian securities legislation and “forward-looking statements” within the meaning of U.S. securities legislation (collectively, “Forward-Looking Information”), which involve known and unknown risks, uncertainties, and other factors which may cause the actual results, performance or achievements of the Company, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such Forward-Looking Information. All statements, other than statements of historical fact, may be Forward-Looking Information, including, but not limited to, mineral resource or mineral reserve estimates (which reflect a prediction of the mineralization that would be realized by development). When used in this AIF, such statements generally use words such as “may”, “would”, “could”, “will”, “intend”, “expect”, “believe”, “plan”, “anticipate”, “estimate” and other similar terminology. These statements reflect management’s current expectations regarding future events and operating performance and speak only as of the date of this AIF. Forward Looking Information involves significant risks and uncertainties, should not be read as guarantees of future performance or results, and does not necessarily provide accurate indications of whether or not such results will be achieved. A number of factors could cause actual results to differ materially from the results discussed in the Forward Looking Information, which is based upon what management believes are reasonable assumptions, and there can be no assurance that actual results will be consistent with the Forward Looking Information.

In particular (but without limitation), this AIF contains Forward Looking Information with respect to the following matters: statements regarding anticipated decision making with respect to the Company; capital expenditure programs; estimates of mineral resources and mineral reserves; development of mineral resources and mineral reserves; government regulation of mining operations and treatment under governmental and taxation regimes; the future price of commodities, including lithium; the realization of mineral resource and mineral reserve estimates, including whether mineral resources will ever be developed into mineral reserves; the timing and amount of future production; currency exchange and interest rates; expected outcome and timing of environmental surveys and permit applications and other environmental matters; potential positive or negative implications of change in government; the Company’s ability to raise capital and obtain project financing; expected expenditures to be made by the Company on its properties; successful operations and the timing, cost, quantity, capacity and quality of production; capital costs, operating costs and sustaining capital requirements, including the cost of construction of the processing plant; and competitive conditions and the ongoing uncertainties and effects in respect of the military conflict in Ukraine.

Forward-Looking Information does not take into account the effect of transactions or other items announced or occurring after the statements are made. Forward-Looking Information is based upon a number of expectations and assumptions and is subject to several risks and uncertainties, many of which are beyond the Company’s control, that could cause actual results to differ materially from those disclosed in or implied by such Forward-Looking Information. With respect to the Forward-Looking Information, the Company has made assumptions regarding, among other things:

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Although management believes that the assumptions and expectations reflected in such Forward-Looking Information are reasonable, there can be no assurance that these assumptions and expectations will prove to be correct. Since Forward-Looking Information inherently involves risks and uncertainties, undue reliance should not be placed on such information.

In addition, Forward Looking Information with respect to the potential outlook and future financial results contained in this AIF is based on assumptions noted above and about future events, including economic conditions and proposed courses of action, based on management’s assessment of the relevant information available as at the date of such information. Readers are cautioned that any such information should not be used for purposes other than for which it is disclosed.

The Company’s actual results could differ materially from those anticipated in any Forward-Looking Information as a result of various known and unknown risk factors, including (but not limited to) the risk factors referred to under the heading “Risk Factors” in this AIF. Such risks relate to, but are not limited to, the following:

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Readers are cautioned that the foregoing lists of assumptions and risks is not exhaustive. The Forward Looking Information contained in this AIF is expressly qualified by these cautionary statements. All Forward Looking Information in this AIF speaks as of the date of this AIF. The Company does not undertake any obligation to update or revise any Forward Looking Information, whether as a result of new information, future events or otherwise, except as required by applicable securities law. Additional information about these assumptions, risks and uncertainties is contained in the Company’s filings with securities regulators, including the Company’s most recent annual a MD&A, which are available on SEDAR at www.sedar.com and on EDGAR at www.sec.gov.

CAUTIONARY NOTE REGARDING MINERAL RESOURCE

AND MINERAL RESERVE ESTIMATES

Technical disclosure included in this AIF regarding the Company’s properties, and in the documents incorporated herein by reference, has not been prepared in accordance with the requirements of U.S. securities laws. Without limiting the foregoing, such technical disclosure uses terms that comply with reporting standards in Canada and estimates are made in accordance with NI 43-101. Unless otherwise indicated, all mineral reserve and mineral resource estimates contained in the technical disclosure have been prepared in accordance with NI 43-101 and the CIM Definition Standards.

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NI 43-101 is a rule developed by the Canadian Securities Administrators that establishes standards for all public disclosure an issuer makes of scientific and technical information concerning mineral projects. NI 43-101 differs significantly from the disclosure requirements of the SEC generally applicable to U.S. companies. Accordingly, information contained in this AIF is not comparable to similar information made public by U.S. companies reporting pursuant to SEC disclosure requirements.

OTHER INFORMATION

Currency

This AIF contains references to United States dollars, Canadian dollars and Brazilian Reais. All dollar amounts referenced, unless otherwise indicated, are expressed in Canadian dollars, referred to herein as “CAD” United States dollars are referred to herein as “US$”. Brazilian Reais are referred to herein as “R$”.

The following table sets forth the high and low, average and period-end exchange rates for one US dollar expressed in Canadian dollars and Brazilian Reais for each period indicated, based upon the daily exchange rates provided by FactSet:

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On April 5, 2024, the rate for Canadian dollars (as quoted by Bloomberg) and Brazilian Reais in terms of the United States dollar was US$1.00 = CAD1.359/R$5.067.

Third Party Information

This AIF includes market, industry and economic data and projections obtained from various publicly available sources and other sources believed by the Company to be true. Although the Company believes these to be reliable, it has not independently verified the information from third party sources, or analyzed or verified the underlying reports relied upon or referred to by the third parties or ascertained the underlying economic and other assumptions relied upon by the third parties. The Company believes that the market, industry and economic data and projections are accurate and that the estimates and assumptions are reasonable, but there can be no assurance as to their accuracy or completeness. The accuracy and completeness of the market, industry and economic data and projections in this AIF are not guaranteed and the Company does not make any representation as to the accuracy or completeness of such information.

Non-GAAP Measures

This AIF and the Restated Technical Report incorporated by reference herein contain certain non-GAAP measures. The non-GAAP measures do not have any standardized meaning within International Financial Reporting Standards (“IFRS”), and therefore may not be comparable to similar measures presented by other companies. These measures provide information that is customary in the mining industry and that is useful in evaluating the Project. This data should not be considered as a substitute for measures of performance prepared in accordance with IFRS.

Qualified Person

Mr. Marc - Antoine Laporte, P.Geo., M.Sc., is the “qualified person” under NI 43-101 who reviewed and approved the technical information disclosed in this AIF and the documents incorporated by reference herein.

Date of Information

Except as otherwise indicated, all information disclosed in this AIF is as of April 30, 2024.

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STRUCTURE OF THE COMPANY

Name, Address and Incorporation

Sigma Lithium Corporation (the “Company” or “Sigma”) is domiciled in Canada and was incorporated under the Canada Business Corporations Act on June 8, 2011 originally under the name Margaux Red Capital Inc. The current business of Sigma was acquired through a reverse take-over transaction on April 30, 2018 pursuant to which the Company acquired Sigma Lithium Resources Inc (“Sigma Holdings”) which held (and continues to hold) the Grota do Cirilo Project, located in the state of Minas Gerais in Brazil (the “Project”) through a Brazilian wholly-owned subsidiary, Sigma Mineração S.A. (“Sigma Brazil”). On completion of the reverse take-over transaction, the Company implemented a share consolidation and changed its name to “Sigma Lithium Resources Corporation”. On July 5, 2021, the Company changed its name to “Sigma Lithium Corporation”.

The registered office of the Company is at Suite 2200, HSBC Building, 885 West Georgia St. Vancouver, BC V6C 3E8 Canada and the head office of the Company is Avenida Nove de Julho 4939, 9th Floor, Torre Europa, Itaim, Sao Paulo, Sao Paulo, 01407-200. The Company’s web site is www.sigmalithium.ca.

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Intercorporate Relationships

The corporate structure of the Company and its subsidiaries (each of which is wholly owned), and their relative jurisdictions of incorporation are set out in the following chart:

GENERAL DEVELOPMENT OF THE BUSINESS

Overview

Sigma is a Canadian-incorporated lithium company, operating what we believe to be one of the largest hard rock lithium mining and beneficiation complexes in the Americas, with an environmental sustainability directed strategy. The Project in Brazil will supply the rapidly expanding lithium-ion battery supply chain for electric vehicles (“EVs”) with sustainable Green Lithium.

For further information on the business of the Company, please refer to “Description of the Business”.

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Three Year History

The following is a summary of the key developments that have generally influenced the development of the Company’s business and projects over the last three fiscal years (and its current fiscal year to date).

2024 to Date

On April 1, 2024, there was a Final Investment Decision for a Phase 2 expansion which will increase production capacity by 250,000 tonnes per annum of spodumene concentrate from Sigma’s Grota do Cirilo operations. Once in production, is expected to light Sigma’s total nameplate capacity to 520,000 tonnes.

On January 31, 2024, Sigma published its updated resource estimate following its 2023 drill campaign. The aggregate measured, indicated and inferred estimate increased to 108.9 million tonnes at an average grading of 1.40% lithium oxide. This was an increase of 27% over the prior estimate of 85.6 million tonnes and a slight decrease in the average grading of lithium oxide at 1.43%. The majority of the revisions were made to the Phase 3 (Nezinho do Chicão) and Phase 4 (Murial) deposits, but the Company also announced a maiden resource estimate of 2.1 million tonnes inferred for its Phase 5, Elvira, prospect.

2023

In 2023, Sigma successfully commissioned and began commercial operations at its Phase 1 lithium production and processing plant (“Greentech Plant”) and mine. During the course of the year, total lithium concentrate production exceeded 105,000 metric tonnes, with operations sustaining annualized nameplate capacity utilization rates of 270,000 metric tonnes for the month of December.

The Company also advanced its plans to triple its lithium concentrate production capacity. This included completing engineering to FEL-3 stage precision of its Phase 2 and 3 Greentech plants. Said plants are to source feedstock ore from the Barreiro and Nezinho do Chicão deposits, which was investigated in the preliminary feasibility study (“PFS”) included in the Restated Technical Report filed on June 12, 2023.

Congruent with its efforts to expand its production footprint were initiatives to build upon its existing resource estimate. In 2023 the Company completed a 30,000 meter drill campaign which resulted in an increase to its overall, pit constrained, measured, indicated and inferred resource estimate as published on January 31, 2024.

In November 2023 the Company actively participated at COP-28, where multiple members of the senior management team hosted workshops on “Impact Investing in Mining.” CEO and Co-Chairperson Ana Cabral-Gardner was featured as a keynote speaker.

On October 6, 2023, Sigma Lithium announced the promotion of Reinaldo Brandao, Keith Prentice and Iran Zan to the positions of Co-General Managers of Mining, Processing and Geology, respectively. The leaders were promoted following the successful commissioning and ramp of the company’s phase 1 Greentech plant and following the departure of company COO, Brian Talbott, for health reasons.

In September 2023 Sigma was also a participant on “Combining Environmental and Social Agendas” panel at the Brazil Climate Summit at Columbia Business School.

On August 11, 2023, Caio Araujo was appointed as Chief Financial Officer of Sigma Lithium following the tenure of interim CFO Rodrigo Menck. Araujo joined Sigma Lithium in June 2023 and has 33 years of experience in finance and controlling, having started his career at PwC. Previously he was CFO at a portfolio company of BTG. Mr. Araujo most recently headed the finance department at CSN, one of the first Brazilian metals and mining companies to register an ADR level on the NYSE, where he implemented the SEC reporting/SOX compliance.

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On June 12, 2023, the Company filed the Restated Technical Report on SEDAR and EDGAR, which includes all of the study results and resource and reserve estimates which were included in the Updated Technical Report, and which includes updated information on the licensing and regulatory approval status of the Project and the Murial drilling program. The Restated Technical Report was prepared by independent mining consultancies and the professional services firms Primero Group Ltd (“Primero”), SGS Canada Inc. (“SGS”), and GE21 Consultoria Mineral (“GE21”) Please refer to “Description of the Business – Current Status of the Project”. For further information on Sigma’s ESG and sustainability programs, please refer to the most recent MD&A of the Company.

On April 17, 2023 the Company announced that it had initiated production of spodumene concentrate from its Phase 1 Greentech Plant. Production followed the successful commissioning of the dense media separation line, after having completed construction and commissioning of the crushing circuit earlier in the year.

2022

In 2022, activity was primarily focused on the construction of the Phase 1 Greentech Plant and pre-mining activities to establish operational readiness ahead of first production. Construction activity progressed throughout the year on schedule, with the Company employing a workforce of more than 1,000 by the fourth quarter of 2022 (approximately 40% comprised of Jequitinhonha Valley region community members, where the Project is located) and crushing circuit commissioning commencing as planned in December 2022.

On December 4, 2022, the results of the Phase 2 & 3 PFS, highlighted a combined Project net present value and internal rate of return of US$15.3 billion and 1,273%, respectively, along with a maiden Phase 3 proven and probable mineral reserve estimate of 21.2 Mt grading at 1.45% Li2O, comprised of 2.2 Mt of proven mineral reserves grading at 1.53% Li2O and 19.0 Mt of probable mineral reserves grading at 1.44% Li2O. The Company later filed the associated Updated Technical Report on SEDAR and EDGAR on January 16, 2023.The Updated Technical Report was prepared by an independent mining consultancies and the professional services firms Primero, SGS, and GE21. This approach was the result of a thorough review of the Company’s strategic priorities, with the objective of potentially responding to a significant increase in demand from its potential customers and solidifying its unique market position as a future supplier of high purity 5.5% battery grade lithium concentrate (“Green Lithium”).

Additionally, on December 4, 2022, the Company secured a US$100,000,000 pre-export financing agreement with Synergy Capital, one of Sigma’s current investors based in the United Arab Emirates (the “Synergy Financing”). The Synergy Financing is a senior secured facility available by way of a multi-draw term loan that contemplates a 48-month term and a borrowing rate of twelve-month BSBY plus 6.95% per annum.

In November 2022, the Company actively participated with its entire ESG leadership team at COP-27 in Egypt. The team collectively participated in more than 25 events, panels, and workshops. Ana Cabral-Gardner was invited by UN-DESA to host a workshop at the SDG Pavilion at COP-27 where it presented a framework to apply UN-SDGs to mining projects globally, in order to measure sustainability and overall economic and social impact. Additionally, Ms. Cabral-Gardner made the keynote presentation on “circular economy” at COP Investments (hosted by the World Climate Fund), presenting the Company strategy to become the first “Zero Tailings” lithium producer by upcycling 100% its hazardous chemicals free” tailings from the Greentech Plant. Ms. Cabral-Gardner also participated at the “Acceleration to Net Zero Series” of McKinsey & Co. at COP-27 with leading sustainability professionals across fields.

On November 17, 2022, to preserve maximum commercial optionality for sales of the Project’s Green Lithium, the Company terminated the heads of agreement that was previously entered into with Mitsui & Co. Ltd. (“Mitsui”) on March 26, 2019 (the “Mitsui HOA”).

On June 22, 2022, the Company estimated a maiden Phase 3 mineral resource of 23.3 Mt of measured and indicated resources grading at 1.49% Li2O and 3.5 Mt of inferred resources grading at 1.48% Li2O. The Company later filed the associated technical report on SEDAR and EDGAR on August 4, 2022.

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On May 25, 2022, the Company filed a technical report associated with an updated Phase 1 feasibility study (the “Phase 1 FS”), a maiden Phase 2 proven and probable mineral reserve estimate of 21.8 Mt grading at 1.37% Li2O, comprised of 16.9 Mt of proven mineral reserves grading at 1.38% Li2O and 4.8 Mt of probable mineral reserves grading at 1.29% Li2O and a Phase 2 preliminary feasibility study (the “Phase 2 PFS”) on SEDAR and EDGAR.

2021

On December 23, 2021, the Company completed a non-brokered private placement (the “December 2021 Offering”) of 11,634,137 Common Shares at a price of CAD11.75 per Common Share for aggregate gross proceeds of CAD136.7 million (approximately US$106 million). Given the strong investor interest, the December 2021 Offering was upsized twice, first by approximately 42% and then subsequently by an incremental 60%. As part of the December 2021 Offering, funds and accounts managed by BlackRock purchased 4,372,766 Common Shares for an aggregate subscription of approximately CAD51.4 million. Concurrently, BlackRock purchased 1,093,191 Common Shares at the same offering price on a secondary basis from the largest shareholder of the Company, A10 Fund, for an aggregate purchase price of approximately CAD12.8 million.

In December 2021, the Company began issuing letters of intent (“LOIs”) for long lead items for the construction of the Phase 1 Greentech Plant as the December 2021 Offering was completed, the front-end engineering and design (“FEED”) was finalized and the final capital expenditure (“CAPEX”) budget with a project execution plan (“PEP”) was completed. Following the successful conclusion of the first phase of FEED, Promon Engenharia Ltda. (“Promon”) and Primero remained engaged by the Company and continued to focus on negotiating and securing long lead items for the construction of the Phase 1 Greentech Plant. Promon and Primero also led the detailed engineering, procurement and construction management (“EPCM”) for the Phase 1 Greentech Plant construction.

On December 2, 2021, the Company filed an amended and restated technical report associated with a Phase 1 feasibility study and a Phase 2 preliminary economic analysis on SEDAR and EDGAR, which made amendments to the technical report previously filed on July 15, 2021.

On September 13, 2021, the Company completed its dual-listing process and the Common Shares began trading in the U.S. on the Nasdaq. The Company is pleased to report that its corporate governance policies and the make up of the Board are compliant with required Nasdaq and SEC governance standards, including Nasdaq’s diversity requirement for a company’s board to have at least one female director and at least one additional diverse director.

On September 8, 2021, there was the appointment of Ana Cabral-Gardner as Co-CEO, then joining Calvyn Gardner, who was previously CEO and also became Co-CEO as well as the new management appointment of Felipe Peres as Chief Financial Officer. The Company also announced the constitution of an ESG Board Committee resulting from the program intended to achieve net zero emissions by 2024 and the issuance of performance-based restricted share units of the Company (“RSUs”) to the then Co-CEOs.

On February 12, 2021, the Company completed a non-brokered private placement (the “February 2021 Offering”) of 9,545,455 Common Shares at a price of CAD4.40 per Common Share for aggregate gross proceeds of CAD42.0 million. The size of the February 2021 Offering reflected a significant upsizing due to strong institutional investor demand.

DESCRIPTION OF THE BUSINESS

Overview

Sigma is a commercial producer of high purity, environmentally conscious, lithium concentrate. The Company’s existing Phase 1 operations and planned tripling of capacity through Phase 2 and 3 expansions represent what we believe to be one of the largest hard rock lithium mining and beneficiation complexes in the Americas. Its assets are located in the municipalities of Araçuaí́ and Itinga in the northeastern part of the state of Minas Gerais, Brazil. The Company owns 100% of the Project indirectly through its wholly-owned subsidiary Sigma Brazil, with the Project area comprised of 29 mineral rights (which include mining concessions, applications for mining concessions, exploration authorizations, applications for mineral exploration authorizations) spread over 185 km², located within the broader 19,000-hectare land package held by Sigma Brazil (containing the Grota do Cirilo, Sao Jose, Genipapo and Santa Clara properties).

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Sigma’s Common Shares are listed and trade under the symbol SGML on the TSXV and Nasdaq.

Lithium Properties

Sigma’s mineral concessions comprise four properties: Grota do Cirilo (the area of the Project where Phase 1 and Phases 2 and 3 are located), and the Sao Jose, Genipapo and Santa Clara properties. The Project consists of 29 mineral rights (which include mining concessions, applications for mining concessions, exploration authorizations, applications for mineral exploration authorizations) spread over 185 km2.

The properties are located in the northeastern part of the state of Minas Gerais, in the municipalities of Araçuaí́ and Itinga, approximately 25 km east of the town of Araçuaí́ and 600 km northeast of Belo Horizonte, the state capital. The Project is approximately 700 km from the Port of Vitoria, from where the Company ships its concentrate to global markets.

Operations

Sigma Lithium’s operations are vertically-integrated, with the Company’s mining activities supplying spodumene bearing material to its Greentech Plant. The Greentech Plant is designed to process 5.2% to 6.0% high purity lithium concentrate (the “Green Lithium”), engineered to the specifications of the Company’s customers in the rapidly expanding lithium-ion battery supply chain for EVs, in an environmentally friendly way through a fully automated and digital dense medium separation (“DMS”) technology process. The Greentech Plant was built after the completion of engineering to the level of FEL-3 stage precision by Primero and extensive testing at the Company’s on-site demonstration pilot plant, which had been in operation since late 2018 and ceased operation upon commissioning of the Company’s Phase 1 Greentech Plant. It is important to mention that the demonstration plant was used to make initial samples that were sent to clients for testing. Samples were not commercialized.

The Greentech Plant operations also produce a low-grade, high-purity, zero-chemical, hypofine by-product (“Green By-Products”) at approximately 1.3% lithium oxide (“Li2O”), which can be sold to strengthen the Company’s ESG-centric approach to pioneer a “zero tailings” environmental sustainability strategy, minimizing the environmental footprint of tailings storage with a positive ecosystem impact, while also generating an additional revenue stream to the Company.

As the Company’s mission statement has been guided by adhering to the highest level of environmental, social and governance (“ESG”) practices since inception in 2012, the Project is being developed in a sustainable way. Additionally, the Company is focused on social programs promoting sustainable development, inclusion (including on the Company’s Board), and upskilling local people in the region where the Company operates. As a result, the Company has committed to the strategies outlined in Table 1 below, to advance the development of the Project in a responsible and sustainable way. The Company is proud to report that it has successfully delivered on its “net zero carbon” program through the purchase of carbon credit “in-setting”, achieving “quintuple zero” production from the onset. Over the long term, Sigma plans to build upon its ESG commitments through more innovative programs including increasing its trucking fleet’s fuel consumption to a target of 50% biofuels.

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Table 1: Summary of Sigma’s ESG-Driven Decisions & Strategies

(1)The Company’s CEO is female (100%); and the Board of Directors has two chairpersons whose one (50%) is female.

(2)The Board of directors has six members, and four of them (67%) are independent.

(3)The Board Committees, which includes “Audit Committee”, “Compensation & Governance”, “ESG Committee” and “Technical Committee” has eight members, and seven of them (88%) are independent.

(4)The Board of directors has two members (33%) that represent women and LGBTQ community.

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The Company is taking a phased approach to its operations, with production at its Phase 1 Greentech Plant and associated mine successfully initiated in April 2023. At 270,000 tonnes per annum of 5.5% spodumene concentrate production capacity, Phase 1 has positioned the Company as a globally relevant, Tier 1, concentrate producer. The Company plans to expand its production footprint through the buildout of Phase 2 and ultimately Phase 3 Greentech Plants, which would nearly triple production from current levels. The existing shared infrastructure built with the Phase 1 Greentech Plant is expected to support these two additional production lines, with each of the phases designed to follow a similar flowsheet as demonstrated at Phase 1.

Figure 1: Overhead view of Greentech Plant, with DMS circuit in foreground and crushing circuit in the background

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Overview of Phase 1 Commissioning and Ramp

Sigma finished construction of its Phase 1 Greentech Plant in calendar 1Q 2023 (January 1 to March 31, 2023), with first commercial production in April 2023. Sigma was able to achieve initial production on schedule as a result of accelerating construction activity in the fourth quarter of 2022, with the construction workforce increasing to more than 1,000 workers. Initial complications with the first of its kind in the lithium market, dry-stacking circuit, were overcome in June 2023. Monthly production increased successively through December 2023, when the facility sustained operations at average annualized nameplate capacity levels. As of the end of the fiscal year of 2023, the Company has achieved the following significant milestones:

Going forward, the Company intends to remain focused on completing the following key workstream in 2024:

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Health & Safety

Health and safety remains one of Sigma’s primary focuses at the construction phase, and the Company is proud to report the operational health and safety strategy:

The Company upholds employee involvement as a core principle in continuously improving the health and safety system. This commitment is reinforced daily through the strengthening of the Internal Accident Prevention Committee.

Phase 2 Development & Final Investment Decision

During 2023, the Company continued to advance development work for a potential Phase 2 or Phase 2 & 3 production expansion, after announcing the results of the Phase 2 & 3 PFS in December 2022. On March 22, 2024, Sigma Lithium Board of Directors made a Final Investment Decision to double production of its unique Quintuple Zero Green Lithium from the current 270,000 tonnes to 520,000 tonnes. The Board of Directors approved the initiation of construction of a second line of its Greentech Industrial Plant (Phase 2) with Capex of $136 million (FEL3).

The Phase 2 & 3 PFS investigated the opportunity to fast-track Phase 3 production and to build a dual plant which could process both Phase 2 and Phase 3 ore feed simultaneously to deliver a greater production increase in 2025 (if warranted by feasibility study) versus the sole Phase 2 expansion originally envisioned in the Phase 2 preliminary feasibility study completed in May 2022. However, as lithium markets have weakened, the Company has shifted its plans back towards a more incremental approach to expansion. Accordingly, the Company engaged its local Phase 1 Engineering, Procurement, Construction Management Company (“EPCM”) contractor to direct engineering and procurement initiatives on a rebuild of its Phase 1 plant, which is expected to nearly double the Company’s existing production capacity.

The Phase 2 Project is expected to increase production capacity by 250,000 tons per annum of spodumene concentrate from Sigma’s Grota do Cirilo operations. Once in production, Phase 2 Project is expected to lift Sigma’s total nameplate capacity to roughly 520,000 tonnes per annum. The Company plans to begin Phase 2 earthworks in April 2024 and is targeting commissioning of the crushing circuit to begin in late 2024.

On April 1st, 2024, the Company announced the final investment decision of Phase 2 Industrial Plant. The Board of Directors approved the construction of the second line, the Phase 2 Greentech Plant, expanding capacity by 250,000 tons per year, with total capital expenditures expected to be $136 million (see Table 4 below). The full license to build and operate the new industrial plant (“Phase 2”) was awarded to the Company in the first quarter of 2024.

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Figure 4: Uses of Cash Analysis for Phase 2 Construction

(*) Construction Capex (construction capital expenditures)

Phase 1 Mining Progress

As of the date of this AIF, the Company has achieved the following significant milestones:

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Refer to Figures 9 to 12 below for a visualization of Phase 1 mining activities and progress as of the date of this AIF. Note that the area marked in red in Figures 9 and 10 highlight exposed ore.

Going forward, the Company intends to remain focused on the following workstreams:

Sigma will employ contract mining, with Fagundes engaged as the Company’s primary mining contractor.

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Note: Red circles in Figures 9 and 10 highlight exposed ore.

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Licensing Updates

Phase 1 Updates

On March 31, 2023, Sigma received an operational license (“LO”) for the Phase 1 north pit and Greentech Plant, and on April 30, 2023, for the Phase 1 south pit, both with an unanimous vote of approval including all the non- governmental organizations involved. This follows the Company filing its request for the LO for the Phase 1 north pit and Greentech Plant on November 16, 2022 and the Phase 1 south pit on January 23, 2023. The receipt of the LO was the last licensing step required for Sigma to produce Green Lithium.

On June 29, 2022, the Grant of Right to Use Water Resources (“Outorga de Direito de Uso de Recursos Hídricos”) was approved, allowing the Company to use pit seepage water for dust suppression and other mining activities.

On June 27, 2022, the Company obtained the requested extension of its current environmental licenses for construction, installation and commissioning from COPAM. The extension allows for the simultaneous mining of the Phase 1 north pit and south pit and also allows for the Company to increase the area utilized for the dry stacking of the tailings of the Greentech Plant.

On June 23, 2022, the State Institute of Historic and Artistic Heritage of Minas Gerais (“Instituto Estadual do Patrimônio Histórico e Artístico de Minas Gerais” or “IEPHA”) approved the Preliminary Cultural Impact Study, which assesses the possibility of impacts of the project on protected cultural assets.

On April 26, 2022, the COPAM, through its Biodiversity Protection Chamber (“CPB”), approved the environmental compensation proposal presented by Sigma for the vegetation suppression to be carried out. According to the proposal, Sigma will compensate for twice the area to be suppressed, through the land regularization of the Mata Escura Biological Reserve, an integral protection conservation unit located in the same hydrographic basin as the Project.

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In January 2022, SUPPRI (the “Priority Projects Superintendence of Minas Gerais”) issued the final request for complementary information (“Complementary Information Request”). In March 2022, the Company fully responded (“Complementary Information Reply”) to the Complementary Information Request. The Complementary Information Reply included the submission to SUPPRI of the following environmental studies: Plano de Tráfego (updated traffic plan); Mapa Desvio Estrada Municipal (map and plan for deviation of municipal road); Relatório Campanhas de Monitoramento (monitoring campaigns report); Relação de Comunidades (itemization and description of each community affected); Programa de Monitoramento das Águas Superficiais (surface water monitoring program); Programa de Monitoramento das Águas Subterrâneas (underground water monitoring program); Informações Não Contempladas no PCA (additional information non-contemplated at PCA); Caracterização Hidrológica do Córrego Taquaral (hydrogeology study of Taquaral seasonal stream); Prospecção Espeleológica (report of any existing caves in the area); Plano de Reaproveitamento do Rejeito (tailings recycling plan); Drenagem Pilhas de Disposição de Rejeito/Estéril (drainage plan for tailings piles); (Implicações Inventário Vegetaçao (vegetation inventory); Programa de Resgate de Espécies da Flora Ameaçadas e Endêmicas (program for rescue of eventual endangered species of vegetation); Licença de Pesca Científica (license for scientific fishing); and Pontos de Monitoramento da Herpetofauna (monitoring points of reptile animals of the region).

Phase 2 Updates

On March 22, 2024, as laid out above, the Sigma Board of Directors issued an FID on the Phase 2 project.

On February 9, 2024, SUPPRI issued the final request for additional information (“Request for Complementary Information for Phase 2”). Sigma is preparing the responses with a protocol expected in March 2024.

On January 31, 2024 Sigma was awarded its preliminary license, along with the installation license and an operational license (“LP”, “LI” and “LO”, respectively) to install and operate its second Greentech Plant by the State of Minas Gerais. The Company, once again, received unanimous approval by all members of the independent State Environmental Policy Council (“COPAM”) including the vote of the board members representing the NGOs (“Non-governmental organizations”). COPAM is the board responsible for voting and awarding environmental licenses in the State of Minas Gerais. The obtainment of the LP, LI and LO for its second Greentech Plant allows the Company to further expand its industrial beneficiation and processing capacity of lithium minerals to up to a total of 3.7 million tonnes per year.

On August 17, 2022, the Company filed at SUPPRI the environmental studies, including, among others, the environmental impact study and environmental mitigation plan (the “Phase 2 EIA/RIMA”) for a preliminary, installation and operational license (“”LP”, “LI” and “LO”, respectivelly) for Phase 2 and its piles. Once the EIA/RIMA is approved by the environmental authorities, the Company will be authorized to commence the construction, installation and operation of Phase 2, if a formal production decision to proceed with Phase 2 & 3 is made.

The Company conducted detailed environmental impact studies for the fauna and the flora in the area of Phase 2 where the pit and waste piles will be located. These studies started in the dry season of the second quarter of 2021 and continued throughout the wet season during the third and fourth quarters of 2021.

The design proposed by the Company in the environmental impact study and environmental mitigation plan for the area directly impacted by the Project (the “Project Impacted Area”) has followed the Company’s ESG-centric approach to minimize distances by combining the minimization of greenhouse gas emissions of diesel in mining trucks with a minimization of semi-arid bush and vegetation suppression. Therefore, the Company contemplated the location of its processing tailings dry stacking piles in the vicinity of the Greentech Plant.

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Exploration Progress

The 2023 exploration campaign focused on expanding resource density within the Grota do Cirilo mineral concessions, with the Company’s combined Measured, Inferred and Indicated tonnages increasing to 108.9Mt grading at 1.40% Li2O, from the previous estimate of 85.6Mt at 1.43% Li2O. Of this newly enlarged resource estimate, 87% comprises the higher confidence Measured and Indicated categories.

Specifically, the Phase 3 orebody (Nezinho do Chicão) was extended eastwards approaching the Phase 4 ore bodies (Maxixe, Tamboril and Lavra do Meio), in so doing consolidating 4 pegmatites into a singular, larger open pit encompassing 40.1Mt of Measured, Indicated and Inferred resource. The remaining Phase 4 (Murial) deposit is to be developed within a separate pit some 330m north of the Phase 3 megapit. The Phase 4 (Murial) deposit has grown in scale to 16.1Mt of combined Measured, Indicated and Inferred resource, notably up from the prior 5.6Mt resource. This new Phase 3 and 4 resource strike extends 3.2km, from the southern end of Nezinho do Chicão to the north end of Murial. Drilling confirms that the deposits remain open to the west and east.

Table 2: Sigma Lithium Consolidated Resource Estimate

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In addition, the exploration program led to the discovery of two additional spodumene-bearing deposits, known as Barreiro Extension and Phase 5 (Elvira). Barreiro Extension is located 550m northwest of the Phase 2 (Barreiro) deposit; the Company is exploring the potential connectivity of these resources. Phase 5 (Elvira) is a cluster of large pegmatites located 4km south of Nezinho do Chicão. The 2023 drill campaign resulted in a maiden resource estimate for Elvira of 2.1Mt of Inferred lithium at an average grade of 1.16% Li2O. However, the Company believes, given drill intercepts to date, that the resource could grow to 20Mt over time.

The Company currently plans to drill approximately 10,000 meters in 2024, with the goal of further increasing the Company’s estimated mineral resources. The Company expects any additional mineral resource growth achieved will be utilized as feedstock material to extend its operating life, if warranted after completing and analyzing a preliminary economic assessment, pre-feasibility study and feasibility study.

Royalties

The Brazilian government levies a royalty on mineral production: Compensação Financeira pela Exploração de Recursos Minerais (“CFEM”). Lithium production is subject to a 2% CFEM royalty, payable on the gross income from sales.

In addition, the Project is also subject to a net smelter return royalty (“NSR Royalty”) owed to LRC LP I (a third-party) of 1% over the gross revenues of the Company from sales of minerals extracted from the Project, less taxes, returns, sales commissions, cost of insurance and freight.

The Project was also subject to an NSR Royalty of 1% to another third-party – Mr. Amilcar de Melo Afgouni (“Amilcar Royalty”). Under the agreement, Sigma Brazil had the option to repurchase the Amilcar Royalty, exercisable at any time, for $4,892 (US$3,800). Mr. Afgouni had the option to require the repurchase of the Amilcar Royalty for the same price, exercisable: (i) if Sigma Brazil commences commercial production and reaches production of 40,000 tons of lithium concentrate per year; or (ii) if the original controlling group of Sigma Holdings ceases to have an indirect interest of at least 30% in Sigma Brazil on a fully diluted basis. As of December 31, 2022, this option amounted to $5,081. Further in 2023, due to the advancement of the Company’s wholly owned Grota do Cirilo lithium project, the Company exercised the option on April 13, 2023 at its fair value for $5,372.

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Surface Rights and Other Permitting

Certain surface rights in the Phase 1 area, the current primary focus of the Company’s activity, are held by Arqueana Empreendimentos e Participações S.A. (“Arqueana”), Miazga Participações S.A. (“Miazga”) and Tatooine Investimentos S.A. (“Tatooine”). The CEO of the Company, Ana Cabral, has indirect economic interests in Arqueana and Miazga and Tatooine is controlled by Marina Bernardini . Arqueana, Miazga and Tatooine have an assignment of surface rights arrangement with Sigma Brazil to support its exploration and development activities within the Grota do Cirilo property, as well as with third-party surface owners in the Project area.

Sigma Brazil has a mining easement with a total of 413.3 hectares (“Servidão Mineral”) and aims to cover areas including: waste and tailings piles, Greentech Plant, all access roads (internal), electrical substation, installation of fueling station and support structures. The Servidão Mineral was published on June 29, 2020 in the Official Gazette of the Federal Government of Brazil. It contemplates the mining and processing activities of Phase 1 (ANM Process No. 824.692/1971).

The Company also obtained a key approval by the National Mining Agency on June 4, 2021 for the Phase 2 plan with the Agência Nacional de Mineração (the “ANM”) approving its economic feasibility study (“Plano Econômico de Avaliação” – PAE). This approval advanced the Phase 2 permitting process to the mining concession request stage (“Requerimento de Concessão de Lavra”).

The Company holds approved economic mining plans (Plano de Aproveitamento Econômico or PAE) over the Xuxa, Barreiro, Lavra do Meio, Murial, and Maxixe deposits within the Grota do Cirilo property. The plan was approved on November 16, 2018 by the National Mining Agency.

Specialized Skills and Knowledge

All aspects of the Company’s business require specialized skills and knowledge. Such skills and knowledge include the areas of geology, drilling, logistics planning and implementation of exploration programs as well as regulatory, finance and accounting. To date, the Company has been able to locate and retain such professionals from Australia, Brazil, Canada, Russia, South Africa and the United Kingdom, and believes it will be able to continue to do so. The Company relies upon its management, employees and various consultants for such expertise.

Mineral Price and Economic Cycles

The mining business is subject to mineral price cycles. The marketability of minerals and mineral concentrates is also affected by worldwide economic cycles. Lithium markets are affected by demands for lithium batteries and global economic conditions. Fluctuations in supply and demand in various regions throughout the world are common.

Economic Dependence

The Company’s business is dependent on the exploration, development and operation of lithium properties and the EV market. The Company does not expect to be dependent on any sole contract to sell the Company’s products or to purchase the Company’s requirements for goods, services or raw materials.

Bankruptcy and Similar Procedures

There are no bankruptcies, receivership or similar proceedings against the Company, nor is the Company aware of any such pending or threatened proceedings. The Company has not commenced any bankruptcy, receivership or similar proceedings during the Company’s history.

Reorganizations

There have been no corporate reorganizations of the Company within the three most recently completed fiscal years.

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Foreign Operations

The Project exposes the Company to various degrees of political, economic and other risks and uncertainties. See “Emerging Market Disclosure” and “Risk Factors” below.

Employees

As of December 31, 2023, the Company had 523 employees working at various locations. During construction periods, the Company’s workforce can reach more than 1,000 people.

Environmental Protection

The current and future operations of the Company, including exploration and development activities, are subject to extensive laws and regulations governing environmental protection, employee health and safety, exploration, development, tenure, production, taxes, labor standards, occupational health, waste disposal, protection and remediation of environment, reclamation, mine safety, toxic substances and other matters. The Company and its subsidiaries are complying with all material aspects of the applicable legislation.

Social and Environmental Policies

The Company aims to minimize the impact of its operations on both local communities and the environment. The Company is committed to developing the Project in a responsible and sustainable manner. The Company takes its responsibilities seriously to protect the environment, to conduct business based on high ethical standards (including a commitment to not engaging in business with any persons or entities subject to multinational sanction) and to make a positive difference in the communities in which it operates.

Life Cycle Analysis and Net Zero Strategy

The Company has engaged Minviro Ltd. for the preparation of an independent ISO 14064 - 3 compliant life cycle assessment (“LCA”). The Company has engaged BeZero Carbon Ltd for the assessment of the Company’s internal carbon offsetting projects (“in-setting projects”) and advice on a portfolio of carbon additional in-setting projects and initiatives which the Company may undertake in order to deliver its plans to make a robust net zero declaration by 2024.

The objectives are to understand the greenhouse gas emissions associated with the positive activities of carbon sequestering undertaken by the Company, link the results to the overall carbon footprint of existing and planned operations, create an in-setting and offsetting plan for residual emissions and provide an evidence-based assessment for the Company’s net zero targets. The Company will take responsibility for all of its expected scope 1, 2, and 3 emissions, as is the expectation in today’s international carbon accounting environment for maximizing the robustness and defensibility of the Company’s strategy. Net zero targets are undertaken in two phases: (i) net zero during 2024: incorporating scope 3 emissions from mine to port of shipment in Brazil; and (ii) deliver its plans to make a robust net zero declaration by 2025: incorporating scope 3 emissions at port of delivery.

The study and the audit are contemplating its production route of Green Lithium with spodumene mining and lithium purification and concentration production in Brazil. The final ISO 14046-3 audit report is ongoing and will include: (i) a cradle to grave life cycle inventory and impact assessment to generate impact data for climate change, water consumption, land use, waste management and certain impact categories selected by the Company; and (ii) a complete contribution analysis outlining the major inputs contributing to the impact categories.

The Company expects to publish results from the Life Cycle Analysis LCA in 2024, including its carbon insetting and off-setting strategies. The Company plans to adapt to the most up to date norms in the industry, as this is an important pillar of the Company’s plans to develop and maintain a net zero strategy, while the expectations and norms for offsetting and emissions reporting continue to evolve.

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SUMMARY OF THE RESTATED TECHNICAL REPORT

Set out below and up to, but excluding the Emerging Market Disclosure, is an extract from the Restated Technical Report dated March 19, 2024, with an effective date of January 18, 2024, prepared by Homero Delboni Jr, B.E., M.Eng.Sc., Ph.D., Marc-Antoine Laporte, P. Geo, Jarrett Quinn, P.Eng., Porfirio Cabaleiro Rodriguez, Meng., and William van Breugel, P.Eng. (the “TR Qualified Persons”). Reference should be made to the full text of the Restated Technical Report, which is the current technical report on the Project, is available on the Company’s website at www.sigmalithium.ca or at the Company’s profile on SEDAR at www.sedar.com and on EDGAR at www.sec.gov and is incorporated by reference into this AIF, for the detailed disclosure in respect of the Project.

All statements in the summary below are as of the effective date of the Restated Technical Report.

Property Description and Location

The Project is located in the northeastern Minas Gerais State, in the municipalities of Araçuaí and Itinga, approximately 25 km east of the town of Araçuaí and 600 km northeast of Belo Horizonte.

The Project is comprised of four properties owned by Sigma Mineração S.A (“SMSA”) and is divided into the Northern Complex (the Grota do Cirilo, Genipapo and Santa Clara properties) and the Southern Complex (the São José property).

The Project consists of 29 mineral rights, which include mining concessions, applications for mining concessions, exploration permits and applications for mineral explorations authorizations, spread over 185 km², and includes nine past producing lithium mines and 11 first-priority exploration targets. Granted mining concessions are in good standing with the Brazilian authorities.

Certain surface rights in the Xuxa area, the current primary focus of mining activity, are held by two companies, Arqueana Minérios e Metais (Arqueana), Miazga Participações S.A. (Miazga) and Tatooine Investimentos S.A. (Tatooine). SMSA has entered into two right-of-way agreements with these companies to support Sigma’s exploration and development activities within the Grota do Cirilo property, as well as with third-party surface owners in the Project area.

SMSA has a mining easement (Servidão Mineral) with a total of 413.3 hectares and aims to cover the areas of waste and tailings piles, production plant, all access roads (internal), electrical substation, installation of fueling station and support structures. The Servidão Mineral was published in the Official Gazette of the Federal Government. It contemplates the mining and processing activities of the Xuxa deposit and processing plant (ANM Process No. 824.692/1971).

The Brazilian Government levies a Compensação Financeira pela Exploração de Recursos Minerais (CFEM) royalty on mineral production. Lithium production is subject to a 2.0% CFEM royalty, payable on the gross income from sales. The Project is subject to one third-party net smelter return (NSR) royalties of 1%.

To the extent known to the QPs, there are no other significant factors and risks that may affect access, title, or the right or ability to perform work on the Project that have not been discussed in this Report.

Accessibility, Climate, Local Resources, Infrastructure and Physiography

The Project is easily accessible from federal paved road BR-367, which runs through the northern part of the Project. Within the Project area, accessibility is provided by municipal roads. A municipal airport services the town of Araçuaí for private flights. The closest major domestic airports are located at the municipality of Vitória da Conquista, 273 km east of the Project and at the municipality of Montes Claros, 329 km west of the Project.

The Eastern Brazil region is characterized by a dry, semi-arid and hot climate. It is expected that future mining operations could be conducted year-round. Exploration activities are year-round but can be interrupted by short-term rainfall events.

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Mining operations have been previously conducted in the Project area. Existing infrastructure includes power supply and substation, an extensive office block equipped with internet and telephones, accommodation for 40 persons on site, dining hall and kitchen, workshop, on-site laboratory and sample storage building, warehouse and a large store, a fuel storage facility with pumping equipment, and a water pumping facility from the Jequitinhonha River with its reservoir. The main 138 kV transmission line from the Irape hydro power station runs through the northern part of the Project area. The towns of Araçuaí and Itinga can supply certain services. Other services may be sourced from Belo Horizonte or São Paulo.

The topography consists of gently rolling hills with less than 100 m difference in elevation. The Project area typically hosts thorn scrub and savannah. Much of the area has been cleared for agriculture. The primary source of water for this project is the Jequitinhonha River.

History

Exploration and mining activities prior to Sigma’s project interest were conducted by Companhia Estanìfera do Brazil (CEBRAS), Arqueana Minérios e Metais (Arqueana), Tanex Resources plc (Tanex; a subsidiary of Sons of Gwalia Ltd (Sons of Gwalia)), and RI-X Mineração S.A. (RI-X). CEBRAS produced a tin/tantalite concentrate from open pit mines from 1957 to the 1980s. Arqueana operated small open pit mines from the 1980s to the 2000s, exploiting pegmatite and alluvial gravel material for tin and tantalite. Tanex Resources obtained a project interest from Arqueana, and undertook channel sampling, air-track, and reverse circulation (RC) drilling. The Project was subsequently returned to Arqueana. In 2012, RI-X obtained a controlling interest in Arqueana, and formed a new subsidiary company to Arqueana called Araçuaí Mineração whose name was later changed to Sigma Brazil. Sigma Brazil completed mapping, data compilation, a ground magnetic survey, channel sampling, and HQ core drilling. A heavy mineral separation (HMS) pilot plant was built during 2014–2015. Lithium-specific mining activities were conducted over at least five deposits in the Northern Complex, and four deposits in the Southern Complex.

In 2017 Sigma purchased a dense media separation (DMS) unit to produce a 6% Li2O spodumene concentrate. Sigma has completed ground reconnaissance, satellite image interpretation, geological mapping, channel and chip sampling, trenching, core drilling, Mineral Resource and Mineral Reserve estimation, and a feasibility study. Sigma initially focused on a geological assessment of available field data to prioritize the 200 known pegmatites that occur on the various properties for future evaluation. A ranking table that highlighted pegmatite volume, mineralogy and Li2O and Ta2O5 grade was established. Within the more prospective areas, Sigma concentrated its activities on detailed geological and mineralogical mapping of historically mined pegmatites, in particular, on the larger pegmatites.

Geological Setting and Mineralization

The pegmatites in the Project area are classified as lithium–cesium–tantalum or LCT types. The Project area lies in the Eastern Brazilian Pegmatite Province (EBP) that encompasses a very large region of about 150,000 km2, stretching from the state of Bahia to Rio de Janeiro state.

The pegmatite swarm is associated with the Neoproterozoic Araçuaí orogeny and has been divided into two main types: anatectic (directly formed from the partial melting of the country rock) or residual pegmatite (fluid rich silicate melts resulting from the fractional crystallization of a parent magma). The pegmatites in the Project area are interpreted to be residual pegmatites and are further classified as LCT types.

Pegmatite bodies are typically hosted in a grey biotite–quartz schist and form bodies that are generally concordant with the schist foliation but can also cross-cut foliation. The dikes are sub-horizontal to shallow-dipping sheeted tabular bodies, typically ranging in thickness from a few meters up to 40 m or more, and display a discontinuous, thin, fine-grained chilled margin. Typical pegmatite mineralogy consists of microcline, quartz, spodumene, albite and muscovite. Spodumene typically comprises about 28–30% of the dike, microcline and albite around 30–35%, and white micas about 5–7%. Locally, feldspar and spodumenes crystals can reach as much as 10–20 cm in length. Tantalite, columbite and cassiterite can occur in association with albite and quartz. The primary lithium-bearing minerals are spodumene and petalite. Spodumene can theoretically contain as much as 3.73% Li, equivalent to 8.03% Li2O, whereas petalite, can contain as much as 2.09% lithium, equivalent to 4.50% Li2O.

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Features of the pegmatites where mineral resources have been estimated include:

Exploration

The development of the Project started in the second quarter of 2012, focusing on a geological assessment of available field data to prioritize the 200 known pegmatites that occur on the various properties for future evaluation. A ranking table that highlighted pegmatite volume, mineralogy and Li2O and Ta2O5 grade was established.

Within the more prospective areas, Sigma concentrated its activities on detailed geological and mineralogical mapping of historically mined pegmatites, and in particular, on the larger pegmatites, Phase 1 and Phase 2. These dikes were channel sampled and subsequently assessed for their lithium, tantalum and cassiterite potential. This work was followed by bulk sampling, drilling and metallurgical test work. In the southern complex area, Sigma geologists have visited sites of historical workings, and undertaken reconnaissance mapping and sampling activities. The Lavra Grande, Samambaia, Ananias, Lavra do Ramom and Lavra Antiga pegmatites were mined for spodumene and heavy minerals, and in some cases gem-quality crystals were targeted. These pegmatites are considered to warrant additional work.

Drilling

Drilling completed by Sigma Brazil across the Project area consists of 458 core holes totalling 82,455 m. To date, this drilling has concentrated on the Grota do Cirilo pegmatites. Drilling was completed using HQ core size (63.5 mm core diameter) in order to recover enough material for metallurgical testing. Drill spacing is variable by pegmatite, but typically was at 50 m with wider spacing at the edges of the drill pattern. Drill orientations were tailored as practicable to the strike and dip of the individual pegmatites. The drill hole intercepts range in thickness from approximately 85–95% of true width to near true width of the mineralization.

All core was photographed. Drill hole collars were picked up in the field using a Real Time Kinematic (RTK) global positioning system (GPS) instrument with an average accuracy of 0.01 cm. All drill holes were down-hole surveyed by Sigma personnel using the Reflex EZ-Track and Reflex Gyro instruments. Calibrations of tools were completed every year since 2017.

Sampling intervals were determined by the geologist, marked and tagged based on lithology and mineralization observations. The typical sampling length was 1 m but varied according to lithological contacts between the mineralized pegmatite and the host rock. In general, 1-2 m host rock samples were collected from each side that contacts the pegmatite.

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Sigma Brazil conducted HQ drilling programs in 2014, 2017, 2018, 2020, 2021 and 2022 on selected pegmatite targets. The drill programs have used industry-standard protocols that include core logging, core photography, core recovery measurements, and collar and downhole survey measurements. There are no drilling, sampling or recovery factors that could materially impact the accuracy and reliability of the results in any of the drill campaigns. Drill results from Grota do Cirilo property support the Mineral Resource and Mineral Reserve (MRMR) estimates for the Phase 1 FS and the Phase 2 & 3 PFS update.

Sample Preparation, Analyses and Security

Sampling intervals were determined by the geologist, marked and tagged based on lithology and mineralization observations. The typical sampling length was 1 m but varied according to lithological contacts between the mineralized pegmatite and the host rock. In general, 1 m host rock samples were collected from each side that contacts the pegmatite.

All samples collected by SMSA during the 2014–2023 exploration programs were sent to the SGS Geosol laboratory (SGS Geosol) located in the city of Belo Horizonte, Brazil. A portion of the 2017–2018 and 2020-2023 sample pulps were prepared by ALS Brazil Ltda. in Vespasiano, Brazil (ALS Vespasiano) and shipped to ALS Canada Inc. Chemex Laboratory (ALS Chemex) in North Vancouver, BC, Canada for cross check validation. A portion of the 2014 samples were resampled by the QP and sent for validation to the SGS Lakefield Laboratory (SGS Lakefield) in Lakefield Canada. All laboratories, including ALS Chemex, ALS Vespasiano, SGS Lakefield and SGS Geosol are ISO/IEC 17025 accredited. The SGS Geosol laboratory is ISO 14001 and 17025 accredited by the Standards Council. All laboratories used for the technical report are independent from SMSA and Sigma and provide services to SMSA pursuant to arm’s length service contracts.

Sample preparation conducted at SGS Geosol consisted of drying, crushing to 75% passing 3 mm using jaw crushers, and pulverizing to 95% passing 150 mesh (106 µm) using a ring and puck mill or a single component ring mill. In 2017, SGS Geosol performed 55-element analysis using sodium peroxide fusion followed by both inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) finish (SGS code ICM90A). This method uses 10 g of the pulp material and returns different detection limits for each element and includes a 10 ppm lower limit detection for Li and a 10,000 ppm upper limit detection for Li. In 2018, SGS Geosol used a 31-element analytical package using sodium peroxide fusion followed by both Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and ICP-MS finish (SGS code ICP90A). The 2020-2022 samples were assayed by SGS Geosol with a 31-element analytical package using sodium peroxide fusion followed by both Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and ICP-MS finish (SGS code ICP90A) For Li, the lower limit of detection is 10 ppm, and the upper limit of detection is 15,000 ppm (1.5% Li).

Sample preparation at ALS Vespasiano comprised drying, crushing to 70% passing 2 mm using jaw crushers, and pulverizing to 85% passing 200 mesh (75 µm) using a ring and puck mill or a single component ring mill. Lithium and boron were determined by sodium peroxide fusion followed by ICP-AES analysis (ALS Chemex method ME-ICP82b).

The 2017 witness samples collected on the 2014 drill core were analyzed at SGS Lakefield using sodium peroxide fusion followed by both ICP-OES and ICP-MS finish (SGS code ICM90A).

In addition to the laboratory quality assurance quality control (QA/QC) routinely implemented by SGS Geosol and ALS Chemex using pulp duplicate analysis, SMSA developed an internal QA/QC protocol for the Xuxa drilling, which consisted of the insertion of analytical standard reference materials (standards), blanks and core duplicates on a systematic basis with the samples shipped to the analytical laboratories. In 2017 and 2021, Sigma also sent pulps from selected mineralized intersections to ALS Chemex for reanalysis. No pulp reanalysis was performed by Sigmain 2013 and 2014. A total of 729 pulp samples from the 2017, 2018, 2020 and 2021 Xuxa, Barreiro, Murial and Lavra do Meio drilling programs were sent to ALS Vespasiano for third-party verification.

SMSA inserted standards in sample batches during the 2014, 2017–2018 and 2020-2022 sampling programs. The 2017–2018 campaign used seven certified standards from African Mineral Standards (AMIS), an international supplier of certified reference materials while the 2020-2022 campaign used four certified AMIS standards. A total of 88 standards were inserted during the 2017 campaign and 315 were inserted during the 2018 campaign, with a further 73 standards submitted in the 2021 campaign and 210 samples submitted in 2021-2022. Results were considered acceptable, and no material accuracy issues were noted.

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During the 2017–2018 and 2020-2022 campaigns SMSA included insertion of analytical blanks in the sample series as part of their internal QA/QC protocol. The blank samples, which are made of fine silica powder provided by AMIS, are inserted an average of one for every 20 samples by the SMSA geologist and subsequently sent to SGS Geosol. The same procedure was used by SMSA for the 2014 drilling campaign. A total of 939 analytical blanks were analysed during the 2014, 2017–2018 and 2020-2022 exploration programs. Results were considered acceptable, and no material contamination issues were noted.

SMSA inserted coarse duplicates every 20th sample in the sample series as part of their internal QA/QC protocol. The sample duplicates correspond to a quarter HQ core from the sample left behind for reference, or a representative channel sample from the secondary channel cut parallel to the main channel. Assay results were considered acceptable between the two sample sets.

Bulk densities of the lithologies were measured by SGS Geosol by pycnometer measurement. Measurements were by lithology with special attention to the lithium bearing pegmatite. Separate measurements were made for the Xuxa, Barreiro, Murial, Lavra do Meio and NDC deposits.

A total of 219 measurements were made on Xuxa core from 2017–2021. Of the 219 measurements, 26 were made on albite-altered pegmatite, 69 on schist, and 121 on lithium-bearing pegmatite. For Barreiro, a total of 471 measurements were made on core from the 2018 and 2021 drill programs. Of the 471 measurements, 94 were made on albite-altered pegmatite, 206 on schist, and 164 on lithium-bearing pegmatite. For Murial, a total of 134 measurements were made by the same method on core from the 2018 drill program. Of the 134 measurements, 32 were made on the albite-altered pegmatite, 58 on the schist and 44 on the lithium bearing pegmatite. For Lavra do Meio, a total of 51 measurement were made by the same method on core from the 2018 drill program. Of the 51 measurements, nine were made on the albite altered pegmatite, 22 on the schist and 20 on the lithium bearing pegmatite. For NDC, a total of 292 lithium-bearing samples had density measurements calculated, comprising 196 spodumene samples and 96 petalite samples.

In 2017, SGS validated the exploration processes and core sampling procedures used by SMSA as part of an independent verification program. The QP concluded that the drill core handling, logging and sampling protocols are at conventional industry standard and conform to generally accept best practices. The chain of custody was followed by SMSA employees, and the sample security procedure showed no flaws. The QP considers that the sample quality is good and that the samples are generally representative.

As additional QAQC, SMSA sent 664 samples from the 2017-2018 Grota do Cirillo drilling campaign to ALS Chemex for analysis using the protocol ME-ICP82b with sodium peroxide fusion. Preparation was done by ALS Vespasiano and the samples were subsequently shipped to Vancouver. The average Li concentration for the original was 6,411.4 ppm Li while the duplicate average was 6,475.9 ppm Li. This indicates a slight bias of the ALS Chemex duplicates which is well within the accepted margin of error.

Sigma sent 65 samples from the 2021 Barreiro drilling campaign to ALS Chemex for check sample analysis using the ALS Chemex protocol ME-ICP82b with sodium peroxide fusion.

The average lithium concentration for the original samples was 6,518.0 ppm Li and the duplicates averaged 6,559.7 ppm Li, with an average difference of 41.7 ppm or 0.6%. The correlation coefficient R2 of 0.9854 suggests a strong correlation and a high similarity between the two sets of samples.

Sigma sent 304 samples from the 2021-2022 NDC drilling campaign to ALS Chemex for check sample analysis using the ALS Chemex protocol ME-ICP82b with sodium peroxide fusion.

The average lithium grade for the original samples was 1.38% Li2O and the duplicates averaged 1.39% Li2O. The correlation coefficient R2 of 0.98 suggests a strong correlation and a high similarity between the two sets of samples.

A total of 216 coarse duplicates and 216 pulp duplicates from NDC were submitted for analysis from the 2021 and 2022 drill programs. For the coarse duplicates, the average of the original samples was 1.44% Li2O, while the duplicates averaged 1.42% Li2O, while the original pulp samples averaged 1.43% Li2O, with the pulp duplicates also averaging 1.43% Li2O.

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Overall, the QP is confident that the system is appropriate for the collection of data suitable for a Mineral Resource estimate and can support Mineral Reserve estimates and mine planning.

Data Verification

Visits to the Project site were conducted by Marc-Antoine Laporte, P.Geo., M.Sc. from September 11 to September 15, 2017, from July 11 to July 17, 2018, from September 18 to 23, 2018, from October 18 to 21, 2021 and from May 30 to June 1, 2022. These visits enabled the QP to become familiar with the exploration methods used by SMSA, the field conditions, the position of the drill hole collars, the core storage and logging facilities and the different exploration targets.

The database for the Project was transmitted to SGS by Sigma as comma separated values (csv) files and regularly updated by Sigma geologists. The database contains data for: collar locations; downhole surveys; lithologies and lithium assays. Upon importation of the data into the SGS proprietary modelling and mineral resources estimation software (Genesis©), SGS conducted a second phase of data validation where any discrepancies were identified and removed from the database, after consultation and verification with Sigma geologists. Finally, SGS conducted random checks on approximately 5% of the assay certificates, to validate the assay values entered in the database.

Witness sampling was undertaken in 2017 on previously sampled mineralized intervals, with the remaining half core cut to quarter core, and the samples submitted to the SGS Lakefield lab for analysis. A total of nine mineralized intervals were sampled to compare the average grade for the two different laboratories. The average for the original samples is 1.61 % Li2O while the average for the control samples is 1.59 % Li2O. The average grade difference is 0.02% which makes a relative difference of 1.28% between the original and the control samples.

Following the data verification process and QA/QC review, the QP is of the opinion that the sample preparation, analysis and QA/QC protocol used by SMSA for the Project follow generally accepted industry standards and that the Project data is of a sufficient quality

Mineral Processing and Metallurgical Testing

Xuxa

Drill core samples from the Xuxa deposit were processed at the SGS Lakefield facility in 2018 and 2022, samples from the Barreiro deposit were tested between November 2020 and May 2021, and samples from the Nezinho do Chicao deposit in 2022. Work conducted on the Xuxa deposit samples included comminution, heavy liquid separation (HLS), REFLUX™ classifier, dense media separation (DMS) and magnetic separation. The Barreiro deposit test work program included sample characterization, grindability testing, HLS and DMS metallurgical test work. The Nezinho do Chicao deposit test work program included sample characterization, mineralogical analyses, HLS, DMS, and magnetic separation. Xuxa

Drill core samples were selected and combined into six variability (Var) samples for a test work program comprising of mineralogical analyses, grindability, HLS, REFLUX™ classifier, DMS, and magnetic separation testing. Flowsheets for lithium beneficiation were developed in conjunction with the test work. The goal was to produce spodumene concentrate grading a minimum 6% Li2O and maximum 1% Fe2O3 while maximizing lithium recovery.

Four HLS tests, at four crush sizes (15.9 mm, 12.5 mm, 9.5 mm, and 6.3 mm) were carried out on each of the six variability samples to evaluate the recovery. The 9.5 mm crush size was selected as the optimum crush size for DMS test work, as it resulted in the highest lithium recovery with minimal fines generation.

The DMS variability samples were each crushed to -9.5 mm and screened into four size fractions: coarse (-9.5 mm/+6.3 mm), fines (-6.3 mm/+1.7 mm), ultrafines (-1.7 mm/+0.5 mm) and hypofines (-0.5 mm). The coarse, fines and ultrafines fractions of each variability sample were processed separately for lithium beneficiation. The REFLUX™ classifier (RC) test work was carried out with a RC-100 unit for mica rejection from the fines and ultrafines fractions only. This test work was conducted at FLSmidth’s Minerals Testing and Research Center in Utah, USA.

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The coarse, fines and ultrafines RC underflow streams of each variability sample were processed separately through DMS. The DMS concentrate from each fraction underwent dry magnetic separation at 10,000 gauss.

The DMS test work flowsheet for the coarse and fines fractions included two passes through the DMS; the first at a lower specific gravity (SG) cut-point (~2.65) to reject silicate gangue and the second pass at a higher SG cut-point (ca. ~2.90) to generate spodumene concentrate. The coarse DMS middlings were re-crushed to -3.3 mm and a two stage HLS test was conducted. The ultrafines DMS test work flowsheet included both a single pass and a double pass DMS circuit at a high SG cut-point (~2.90) to generate spodumene concentrate.

The DMS test results demonstrated the ability to produce spodumene concentrate with >6% Li2O in most of the tests. Based on the test work results, a lithium recovery of 60.4% was selected for plant design.

Barreiro

Four variability and one composite sample were tested for Barreiro, with the goals of the program to provide preliminary process information on the metallurgical performance of mineralized material from the Barreiro deposit. The test work program was developed based on the flowsheet developed for the Xuxa deposit. The aim of the test work program was to produce chemical grade spodumene concentrate (>6% Li2O) with low iron content (<1% Fe2O3), while maximizing lithium recovery.

Two sets of HLS tests were undertaken. The first set was conducted using the Composite to test optimal crush size (i.e., top size of 15.9 mm, 12.5 mm, 10.0 mm, and 6.3 mm). HLS tests were then performed on each variability sample at the optimum crush size. The fine fraction (i.e., -0.5 mm) was screened out from each sub-sample and the oversize fraction was submitted for HLS testing. A crush size of -10 mm was determined to be optimal and variability HLS testing was undertaken at this crush size. Interpolated stage recoveries (6% Li2O concentrate) for the four variability samples ranged from 56.0% to 77.3%.

In all four variability samples, HLS tests produced >6% Li2O spodumene concentrate with low iron content (<1.0% Fe2O3).

Pilot-scale DMS test work was operated on the composite sample. Dry magnetic separation was undertaken on the DMS feed. DMS test work results showed combined spodumene concentrate grade of 6.11% Li2O and stage recovery of 59.5% for a global recovery of 50.9%.

Nezinho do Chicao

Three variability samples and one composite sample were tested for Nezinho do Chicao (NDC), with the goal of the program to provide process information on the metallurgical performance of mineralized material from the NDC deposit. The test work program was developed based on the flowsheet developed for the Barreiro deposit. The aim of the test work program was to produce chemical grade spodumene concentrate (>5.5% Li2O) with low iron content (<1% Fe2O3), while maximizing lithium recovery.

HLS tests were undertaken across four different crush sizes (i.e., top size of 15.9 mm, 12.5 mm, 9.5 mm, and 6.3 mm) to determine the optimum crush size, for each ore (high grade, medium grade and low grade). The fine fraction (i.e., -0.5 mm) was screened out from each sub-sample and the oversize fraction was submitted for HLS testing. A crush size of -9.5mm was determined to be optimal and variability HLS testing was undertaken at this crush size. Interpolated stage recoveries (5.5% Li2O concentrate) for the three variability samples ranged from 58.7% to 61.4%, and the master composite a nominal 57.8%, for the 9.5mm crushed process step 1.54% Li2O head grade.

Pilot-scale DMS test work was operated on the composite sample. Dry magnetic separation was undertaken on the DMS feed. DMS test work results showed combined spodumene concentrate grade with petalite 5.50% Li2O and stage recovery of 58.7% for a global recovery of 50.6%.

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Mineral Resource Estimates

Mineral Resources for the Grota do Cirilo project were estimated using a computerised resource block model. Three-dimensional wireframe solids of the mineralisation were defined using drill hole Li2O analytical data.

Data were composited to 1 m composite lengths, based on the north–south width of the block size defined for the resource block model. Compositing starts at the schist-pegmatite contact. No capping was applied on the analytical composite data. The Xuxa model used a 5 m x 3 m x 5 m block size and while the Barreiro, Murial, Lavra do Meio, Nezhino do Chicao, Maxixe, Tamboril and Elvira models used a 5 m x 5 m x 5 m block. Average densities were applied to blocks, which varied by pegmatite, from 2.65 t/m3 at Lavra do Meio to 2.71 t/m3 at Barreiro.

Variography was undertaken for Xuxa, Barreiro, NDC and Murial models and the projection and Z-axis rescaling were done according to the mineralization orientation.

The grade interpolation for the Xuxa, Barreiro, NDC and Murial resource block models were completed using ordinary kriging (OK). The Lavra do Meio, Maxixe, Tamboril and Elvira models were estimated using an inverse distance weighting to the second power (ID2) methodology. The interpolation process was conducted using three successive passes with more inclusive search conditions from the first pass to the next until most blocks were interpolated.

The estimates and models were validated by statistically comparing block model grades to the assay and composite grades, and by comparing block values to the composite values located inside the interpolated blocks. The estimates were considered reasonable.

Mineral Resources are classified into Measured, Indicated and Inferred categories. The Mineral Resource classification is based on the density of analytical information, the grade variability and spatial continuity of mineralization.

Conceptual economic parameters were used to assess the reasonable prospects of eventual economic extraction. A series of economic parameters were estimated to represent the production cost and economic prospectivity of an open pit mining operation in Brazil and came either from SGS Canada or SMSA. These parameters are believed to be sufficient to include all block models in future open pit mine planning, due mostly to the relatively low mining costs in Brazil.

The combined Mineral Resource estimate for the Grota do Cirilo project is reported in Table 1-1, while the individual MREs for the different pegmatites are reported in Table 1-2 to Table 1-9 using a 0.3% Li2O cut-off. The Mineral Resource estimates are constrained by the topography and are based on the conceptual economic parameters. The Xuxa estimate has an effective date of the 10th january 2019, the Barreiro estimate has an effective date of the 10th February 2022, and the NDC, Murial, Lavra do Meio, Maxixe, Tamboril and Elvira estimates have an effective date of the 18th January 2024. The QP for the estimates is Mr. Marc-Antoine Laporte, P.Geo., an SGS employee.

Table 0-1: Grota do Cirilo Complete Mineral Resource Estimate

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Notes to accompany Mineral Resource table:

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Table 0-2: NDC Deposit Mineral Resource Estimate

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Table 0-3: Murial Deposit Mineral Resource Estimate

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Table 0-4: Lavra do Meio Deposit Mineral Resource Estimate

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Table 0-5: Maxixe Deposit Mineral Resource Estimate

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Table 0-6: Tamboril Deposit Mineral Resource Estimate

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Table 0-7: Elvira Deposit Mineral Resource Estimate

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Notes to accompany Mineral Resource table:

Table 0-8: Xuxa Deposit Mineral Resource Estimate

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Notes to accompany Mineral Resource table:

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Table 0-9: Barreiro Deposit Mineral Resource Estimate

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Notes to accompany Mineral Resource table:

Factors that can affect Grota do Cirilo Mineral Resource estimates include but are not limited to:

Mineral Reserve Estimates

Xuxa Mineral Reserves

Phase 1 mineral reserve estimates have an effective date of June, 26 2021 and have been converted from Measured and Indicated Mineral Resources. The key parameters upon which the June, 26 2021 Mineral Reserve estimates were defined are summarized in Table 1-6.

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Table 1-6 – Parameters Used in Phase 1 Pit Optimization