•

Key permitting milestone achieved with issuance by BLM of the Draft EIS in April.

•

Draft EIS 45-day public comment period expected to conclude June 3.

•

Rhyolite Ridge Project moves one step closer toward construction.

•

Updated Estimated timeline

o

ROD anticipated by BLM to be October 2024.

o

FID anticipated by Management as December 2024.

Chad Yeftich Ioneer USA Corporation	Ian Bucknell   Ioneer Limited
Investor Relations (USA)	Investor Relations (AUS)
T: +1 775 993 8563	T: +61 434 567 155
E: ir@ioneer.com	E: ibucknell@ioneer.com

Date Released	Title
30/01/2024	December 2023 – Quarterly Activities Report
30/01/2024	December 2023 – Quarterly Cash Flow Report
01/02/2024	Application for quotation of securities - INR
01/02/2024	Change of Director’s Interest Notice – M Walker
01/02/2024	Change of Director’s Interest Notice – R McKinney-James
05/02/2024	Change of Director’s Interest Notice – A Davies
21/02/2024	Half Yearly Report and Accounts
23/02/2024	Change in substantial holding
26/02/2024	BMO 2024 Global Critical Minerals Conference Presentation

Appendix 1 - Schedule of Tenements

 

ASX listing rule 5.3.3

On 16 September 2021, the Company announced a strategic investment by Sibanye-Stillwater7 in the Rhyolite Ridge Project. Under the terms of the agreement, Sibanye-Stillwater will contribute US$490 million for a 50% interest in the Joint Venture, with Ioneer to maintain a 50% interest and retain operatorship. Ioneer has also agreed to provide Sibanye-Stillwater with an option to participate in 50% of the North Basin, upon the election of Sibanye-Stillwater to contribute up to an additional US$50 million, subject to certain terms and conditions. Establishment of the Joint Venture and Sibanye-Stillwater’s funding commitment is subject to certain terms and conditions precedent, including receipt of final permits, commitments for remaining debt financing, and other customary approvals.

 

7 Refer ASX release titles ‘Sibanye-Stillwater to invest US$490M in Rhyolite Ridge’ announced on 16 September 2021.

Name of entity
ioneer Ltd
ABN		Quarter ended (“current quarter”)
76 098 564 606		March 2024

Consolidated statement of cash flows		Current quarter $US’000	Year to date (9 months) $US’000
1.	Cash flows from operating activities	-	-
1.1	Receipts from customers
1.2	Payments for	-	-
	(a)          exploration & evaluation (if expensed)
	(b)          development	-	-
	(c)          production	-	-
	(d)          staff costs	(1,127)	(2,864)
	(e)          administration and corporate costs	(485)	(4,078)
1.3	Dividends received (see note 3)	-	-
1.4	Interest received	209	1,092
1.5	Interest and other costs of finance paid	-	-
1.6	Income taxes paid
1.7	Government grants and tax incentives	-	-
1.8	Other (provide details if material)	-	-
1.9	Net cash from / (used in) operating activities	(1,403)	(5,850)
2.	Cash flows from investing activities	-	-
2.1	Payments to acquire:
	(a)          entities
	(b)          tenements	-	-
	(c)          property, plant and equipment	-	(3)
	(d)          exploration & evaluation (if capitalised)	(8,859)	(30,730)
	(e)          investments	-	-
	(f)          other non-current assets	-	-

	Consolidated statement of cash flows	Current quarter $US’000	Year to date (9 months) $US’000
2.2	Proceeds from the disposal of:	-	-
	(a)          entities
	(b)          tenements	-	-
	(c)          property, plant and equipment	-	-
	(d)          investments	-	-
	(e)          other non-current assets	-	-
2.3	Cash flows from loans to other entities	-	-
2.4	Dividends received (see note 3)	-	-
2.5	Other (provide details if material)	-	-
2.6	Net cash from / (used in) investing activities	(8,859)	(30,733)
3.	Cash flows from financing activities	-	-
3.1	Proceeds from issues of equity securities (excluding convertible debt securities)
3.2	Proceeds from issue of convertible debt securities	-	-
3.3	Proceeds from exercise of options	-	54
3.4	Transaction costs related to issues of equity securities or convertible debt securities	(2)	(11)
3.5	Proceeds from borrowings	1,200	1,200
3.6	Repayment of borrowings	-	-
3.7	Transaction costs related to loans and borrowings	-	-
3.8	Dividends paid	-	-
3.9	Other (provide details if material)	(29)	(94)
3.10	Net cash from / (used in) financing activities	1,169	1,149
4.	Net increase / (decrease) in cash and cash equivalents for the period
4.1	Cash and cash equivalents at beginning of period	27,988	52,709
4.2	Net cash from / (used in) operating activities (item 1.9 above)	(1,403)	(5,850)
4.3	Net cash from / (used in) investing activities (item 2.6 above)	(8,859)	(30,733)
4.4	Net cash from / (used in) financing activities (item 3.10 above)	1,169	1,149

	Consolidated statement of cash flows	Current quarter $US’000	Year to date (9 months) $US’000
4.5	Effect of movement in exchange rates on cash held	135	1,755
4.6	Cash and cash equivalents at end of period	19,030	19,030

5.	Reconciliation of cash and cash equivalents at the end of the quarter (as shown in the consolidated statement of cash flows) to the related items in the accounts	Current quarter $US’000	Previous quarter $US’000
5.1	Bank balances	7,885	12,466
5.2	Call deposits	11,146	15,522
5.3	Bank overdrafts	-	-
5.4	Other (provide details)
5.5	Cash and cash equivalents at end of quarter (should equal item 4.6 above)	19,031	27,988

6.	Payments to related parties of the entity and their associates	Current quarter $US’000
6.1	Aggregate amount of payments to related parties and their associates included in item 1	278
6.2	Aggregate amount of payments to related parties and their associates included in item 2
	Note: if any amounts are shown in items 6.1 or 6.2, your quarterly activity report must include a description of, and an explanation for, such payments

Directors’ fees – 102.6 Executive salary component of chairman’s fee – 78.0 Wages – 97.2

7.	Financing facilities Note: the term “facility’ includes all forms of financing arrangements available to the entity. Add notes as necessary for an understanding of the sources of finance available to the entity.	Total facility amount at quarter end $US’000	Amount drawn at quarter end $US’000
7.1	Loan facilities	-	-
7.2	Credit standby arrangements	-	-
7.3	Other (please specify)	1,200	1,200
7.4	Total financing facilities	1,200	1,200
7.5	Unused financing facilities available at quarter end		-
7.6	Include in the box below a description of each facility above, including the lender, interest rate, maturity date and whether it is secured or unsecured. If any additional financing facilities have been entered into or are proposed to be entered into after quarter end, include a note providing details of those facilities as well.
Lender: Stillwater Mining Company Lender Parent: Sibanye Stillwater Limited Amount: US$1,200,000 Maturity date: Loan will mature and repaid in full 30 days following the termination of the unit purchase agreement (agreement to make an equity investment) by either party. Interest rate: 0% to maturity date. If unpaid by maturity date, then the interest will be accrued at the Secured Overnight Financing Rate (SOFR) plus 8% per annum. Secured/not secured: Not secured.

8.	Estimated cash available for future operating activities	$US’000
8.1	Net cash from / (used in) operating activities (Item 1.9)	(1,403)
8.2	Capitalised exploration & evaluation (Item 2.1(d))	(8,859)
8.3	Total relevant outgoings (Item 8.1 + Item 8.2)	(10,262)
8.4	Cash and cash equivalents at quarter end (Item 4.6)	19,030
8.5	Unused finance facilities available at quarter end (Item 7.5)	-
8.6	Total available funding (Item 8.4 + Item 8.5)	19,030
8.7	Estimated quarters of funding available (Item 8.6 divided by Item 8.3)	1.9
8.8	If Item 8.7 is less than 2 quarters, please provide answers to the following questions:
	1.          Does the entity expect that it will continue to have the current level of net operating cash flows for the time being and, if not, why not?
	Answer: No, the Company expects it will decrease the current level of cash used in operating activities with the completion of drilling in January 2024.
	2.          Has the entity taken any steps, or does it propose to take any steps, to raise further cash to fund its operations and, if so, what are those steps and how likely does it believe that they will be successful?

	Answer:The Company continues to monitor market conditions and manages its cash reserves prudently. The Company regularly assesses its budgeted expenditure and the capital markets with a view to raising capital at a time most beneficial to long term shareholder value, and has announced today completion of its capital raising of A$38.4m in the announcement and “Investor Presentation” lodged with the ASX.  The shares to be issued pursuant to this capital raising will be issued on 6 May 2024. In the March quarter, Sibanye-Stillwater contributed US$1.2 million toward the drilling of Phase 3B holes at the Rhyolite Ridge Project.
	3.          Does the entity expect to be able to continue its operations and to meet its business objectives and, if so, on what basis?
	Answer: Yes, the Company expects to continue its operations and meet its objectives using the measures outlined in 8.8.2.

1	This statement has been prepared in accordance with accounting standards and policies which comply with Listing Rule 19.11A.

2	This statement gives a true and fair view of the matters disclosed.

	30 April 2024
Date:

1.

This quarterly cash flow report and the accompanying activity report provide a basis for informing the market about the entity’s activities for the past quarter, how they have been financed and the effect this has had on its cash position. An entity that wishes to disclose additional information over and above the minimum required under the Listing Rules is encouraged to do so.

2.

If this quarterly cash flow report has been prepared in accordance with Australian Accounting Standards, the definitions in, and provisions of, AASB 6: Exploration for and Evaluation of Mineral Resources and AASB 107: Statement of Cash Flows apply to this report. If this quarterly cash flow report has been prepared in accordance with other accounting standards agreed by ASX pursuant to Listing Rule 19.11A, the corresponding equivalent standards apply to this report.

3.	Dividends received may be classified either as cash flows from operating activities or cash flows from investing activities, depending on the accounting policy of the entity.

4.

If this report has been authorised for release to the market by your board of directors, you can insert here: “By the board”. If it has been authorised for release to the market by a committee of your board of directors, you can insert here: “By the [name of board committee – e.g. Audit and Risk Committee]”. If it has been authorised for release to the market by a disclosure committee, you can insert here: “By the Disclosure Committee”.

5.

If this report has been authorised for release to the market by your board of directors and you wish to hold yourself out as complying with recommendation 4.2 of the ASX Corporate Governance Council’s Corporate Governance Principles and Recommendations, the board should have received a declaration from its CEO and CFO that, in their opinion, the financial records of the entity have been properly maintained, that this report complies with the appropriate accounting standards and gives a true and fair view of the cash flows of the entity, and that their opinion has been formed on the basis of a sound system of risk management and internal control which is operating effectively.

Appendix A

Mineral Resource Statement and Parameters

A summary of the April 2024 Mineral Resource estimate is provided in the table below.

April 2024 Mineral Resource Estimate for Rhyolite Ridge South Basin

Notes:

H3BO3 = boric acid; kt = thousand to

2.  Totals may differ due to rounding, Mineral Resources reported on a dry in-situ basis. Lithium is converted to Equivalent Contained Tonnes of Lithium Carbonate (Li2CO3) using a stochiometric conversion factor of 5.322, and boron is converted to Equivalent Contained Tonnes of Boric Acid (H3BO3) using a stochiometric conversion factor of 5.718. Equivalent stochiometric conversion factors are derived from the molecular weights of the individual elements which make up Lithium Carbonate (Li2CO3) and Boric Acid (H3BO3).

3.  The statement of estimates of Mineral Resources has been compiled by Mr. Herbert E. Welhener, a Competent Person who is a Registered Member of the SME (Society for Mining, Metallurgy, and Exploration), and is a QP Member of MMSA (the Mining and Metallurgical Society of America). Mr Welhener is a full-time employee of Independent Mining Consultants, Inc. and is independent of Ioneer and its affiliates. Mr Welhener has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves’ (JORC Code 2012).

4.  All Mineral Resource figures reported in the table above represent estimates at April 19, 2024. Mineral Resource estimates are not precise calculations, being dependent on the interpretation of limited information on the location, shape and continuity of the occurrence and on the available sampling results. The totals contained in the above table have been rounded to reflect the relative uncertainty of the estimate.

5.  Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code – JORC 2012 Edition).

6.  The Mineral Resource estimate is the result of determining the mineralized material that has a reasonable prospect of economic extraction. In making this determination, constraints were applied to the geological model based upon a pit optimization analysis that defined a conceptual pit shell limit. The conceptual pit shell was based upon a net value per tonne calculation including a 5,000ppm boron cut-off grade for high boron – high lithium (HiB-Li) mineralization (Stream 1) and 1,090ppm lithium cut-off grade for low boron (LoB-Li) mineralization below 5,000ppm boron broke in to two material types low clay and high clay material respectfully (Stream 2 and Stream 3). The pit shell was constrained by a conceptual Mineral Resource optimized pit shell for the purpose of establishing reasonable prospects of eventual economic extraction based on potential mining, metallurgical and processing grade parameters identified by mining, metallurgical and processing studies performed to date on the Project. Key inputs in developing the Mineral Resource pit shell included a 5,000ppm boron cut-off grade for HiB-Li mineralization, 1,090ppm lithium cut-off grade for LoB-Li low clay mineralization and 1,090 ppm lithium cut-off grade for LoB-Li high clay mineralization; mining cost of US$1.54 /tonne; plant feed processing and grade control costs which range between US$52.34/tonne and US$87.43/tonne of plant feed (based on the acid consumption per seam based on the mineral resource average grades); boron and lithium recovery for Stream 1 of 80.2% and 85.7%; Stream 2 and 3: M5 65% and 78%, B5 80% and 86%, S5 50% and 88%, L6 37% and 85%,  respectively; boric acid sales price of US$1,016.67/tonne; lithium carbonate sales price of US$17,868.50/tonne.

In December 2022, the United States Fish and Wildlife Service (USFWS) listed Tiehm’s buckwheat as an endangered species under the Endangered Species Act (ESA) and has designated critical habitat by way of applying a 500 m radius around several distinct plant populations that occur on the Project site. ioneer is committed to the protection and conservation of the Tiehm’s buckwheat. The Project’s Mine Plan of Operations submitted to the BLM in July 2022 and currently under NEPA review has no direct impact on Tiehm’s buckwheat and includes measures to minimise and mitigate for indirect impacts within the designated critical habitat areas identified.

The mineral resource pit shell used to constrain the April 2024 mineral resource estimate was not adjusted to account for any impacts from avoidance of Tiehm’s buckwheat or minimisation of disturbance within the designated critical habitat. Environmental and permitting assumptions and factors have not been taken into consideration during modifying factors studies for the Project. The tonnes and grade within the avoidance polygons have not been removed from the Mineral Resources for the April 2024 estimate. Environmental and permitting assumptions and factors may be taken into consideration during future modifying factors studies for the Project. These permitting assumptions and factors may result in potential changes to the Mineral Resource footprint in the future.

Comparison with Previous Resource

The Table below presents a summary comparison of the current April 2024 Mineral Resource estimate against the previous Mineral Resource estimate for the Project, prepared by Golder (now WSP) in March 2023 in association with the 2023 JORC Mineral Resource Statement.

The updated April 2024 Mineral Resource estimate has been constrained by applying a 5,000 ppm Boron cut-off grade to HiB-Li mineralisation within the B5, M5, S5 and L6 geological units (Stream 1) as well as a 1,090 ppm Lithium cut-off grade to LoB-Li low clay mineralisation in the M5, B5, S5 and L6 geological units (Stream  2) and LoB-Li high clay mineralization in the M5 geological unit (Stream 3). All three styles of mineralisation have also been constrained by the application of a single high-level optimised resource pit shell.

Relative to the March 2023 Mineral Resource estimate, the updated April 2024 Mineral Resource estimate for the Project reflects a small reduction in the estimated resource tonnes and grades.  The impacts to this reduction include:

The updated Mineral Resource estimate also presents a net expansion of the constraining Mineral Resource pit shell. Additional exploration drilling conducted November 2022-December 2023 has allowed for expansion of the resource to the south and east, expanding the 3 square kilometre (km2) area as the March 2023 to 4.67 kilometre (km2) for the April 2024 Mineral Resource.

Summary of Resource Estimate Parameters and Reporting Criteria

In accordance with ASX Listing Rules and the JORC Code (2012 Edition), a summary of the material information used to estimate the Mineral Resource is summarised below (for further information please refer to Table 1 in Appendix D).

Geology and Geological Interpretation

Drilling Techniques and Hole Spacing

Sampling and Sub-Sampling Techniques

Sampling Analysis Method

Cut-off Grades

•

Key input parameters and assumptions for the Mineral Resource pit shell included the following:

Estimation Methodology

Classification Criteria

Mining and Metallurgical Methods and Parameters

The following table provides a summary of important assessment and reporting criteria used at the ioneer Ltd. Rhyolite Ridge Project (the Project) for the reporting of exploration results and Lithium-Boron Mineral Resources and Ore Reserves in accordance with the Table 1 checklist in The Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves (The JORC Code, 2012 Edition). Table 1 is a checklist or reference for use by those preparing Public Reports on Exploration Results, Mineral Resources, and Ore Reserves.

JORC TABLE 1

SECTION 1 SAMPLING TECHNIQUES AND DATA

(Criteria listed in this section apply to all succeeding sections.)

SECTION 2 REPORTING OF EXPLORATION RESULTS

(Criteria listed in the preceding section also apply to this section.)

	Criteria		JORC Code 2012 Explanation		Commentary
	Relationship between mineralisation widths and intercept lengths		•      These relationships are particularly important in the  reporting of Exploration Results.		•   All drill hole intercepts presented in the Report are down hole thickness not true thickness. As discussed in the Orientation of Data section of this Table 1, most drill hole intercepts are approximately orthogonal to the dip of the beds (intercept angles between 70-90 degrees).
			•       If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be  reported.		•   Based on the geometry of the mineralization, it is reasonable to treat all samples collected from inclined drill holes at intercept angles of greater than 70 degrees as representative of the true thickness of the zone sampled.
			•      If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (e.g. ‘down hole length, true width not known’).		•     Not applicable as individual down hole intercepts or Exploration Results are not being reported.
	Diagrams		•     Appropriate maps and sections (with scales) and tabulations of intercepts should be included for any significant discovery being reported These should include, but not be limited to a plan view of drill hole collar locations and appropriate sectional views.		•     Appropriate plan maps and sections are appended to the Report.
	Balanced reporting		•    Where comprehensive reporting of all Exploration Results is not practicable, representative reporting of both low and high grades and/or widths should be practiced to avoid misleading reporting of Exploration Results.		•     Exploration Results are not being reported.
	Other substantive exploration data		•     Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk samples – size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances.		•    Surficial geological mapping performed by a senior ioneer geologist was used in support of the drill holes to define the outcrops and subcrops as well as bedding dip attitudes in the geological modelling. Mapped geological contacts and faults were imported into the model and used as surface control points for the corresponding beds or structures. •  Magnetic and Gravity geophysical survey’s were performed and interpreted to inform the geological model, particularly in the identification of faulting and geologic structures.
	Further work		•     The nature and scale of planned further work (e.g. tests for lateral extensions or depth extensions or large-scale step- out drilling).		•    Additional in-fill drilling and sampling may be performed based on the results of current mining project studies
			•      Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive.		•     Refer to Figure 1 in the body of this report.

	Criteria		JORC Code 2012 explanation		Commentary
	Database integrity		•        Measures taken to ensure that data has not been corrupted by, for example, transcription or keying errors, between its initial collection and its use for Mineral Resource estimation purposes.		•     Measures taken to ensure the data has not been corrupted by transcription or keying errors or omissions included recording of drill hole data and observations by the logging geologists using formatted logging sheets in Microsoft (MS) Excel. Data and observations entered into the logging sheets were reviewed by senior ioneer and Newfield’s geologists prior to importing the data into the MS Access drill hole database. •    IMC evaluated the tabular data provided by ioneer for errors or omissions as part of the data validation procedures described in the following section.
			•        Data validation procedures used.		•     IMC performed data validation on the drill hole database  records using available underlying data and documentation including but not limited to original drill hole descriptive logs, core photos and laboratory assay certificates. Drill hole data validation checks were performed using a series of in-house data checks to evaluate for common drill hole data errors including, but not limited to, data gaps and omissions, overlapping lithology or sample intervals, miscorrelated units, drill hole deviation errors and other indicators of data corruption including transcription and keying errors. •    Database assay values for every sample were visually compared to the laboratory assay certificates to ensure the tabular assay data was free of errors or omissions by Golder for the 2020 resource estimate.  IMC compared database to certificates for  about 20% of the  phase 2 and 3 drill holes and found no errors.
	Site visits		•         Comment on any site visits undertaken by the Competent Person and the outcome of those visits.		•     The IMC Competent Person Herbert E. Welhener made a personal site inspection, this visit was performed on the Project site on August 10th 2023 for the Project. •     During the site visit the IMC Competent Person visited the ioneer core shed in Tonopah NV, and the South Basin area of the Rhyolite Ridge Project site, which is the focus of the current exploration and resource evaluation efforts by ioneer.

	Criteria		JORC Code 2012 explanation		Commentary
					•    The IMC Competent Person observed the active drilling, logging and sampling process and interviewed site personnel regarding exploration drilling, logging, sampling and chain of custody procedures. •    The outcome of the site visit was that the IMC Competent Person developed an understanding of the general geology of the Rhyolite Ridge Project. The IMC Competent Person was also able to visually confirm the presence of a selection of monumented drill holes from each of the previous drilling programs as well as to observe drilling, logging and sampling procedures during the current drilling program and to review documentation for the logging, sampling and chain of custody protocols for previous drilling programs.
			•    If no site visits have been undertaken indicate why this is the case.		•     Not applicable.
	Geological interpretation		•   Confidence in (or conversely, the uncertainty of) the geological interpretation of the mineral deposit.		•  The IMC Competent Person is confident that the geological interpretation of the mineral deposit is reasonable for the purposes of Mineral Resource estimation.
			•   Nature of the data used and of any assumptions made.		•   The data used in the development of the geological interpretation included drill hole data and observations collected from 104 core and 50 RC drill holes, supplemented by surface mapping of outcrops and faults performed by ioneer personnel. Regional scale public domain geological maps and studies were also incorporated into the geological interpretation. •      It is assumed that the mineralized zones are continuous  between drill holes as well as between drill holes and surface mapping. It is also assumed that grades vary between drill holes based on a distance-weighted interpolator.
			•   The effect, if any, of alternative interpretations on Mineral Resource estimation.		•    There are no known alternative interpretations.
			•   The use of geology in guiding and controlling Mineral Resource estimation.		•    Geology was used directly in guiding and controlling the Mineral Resource estimation. The mineralized zones were modelled as stratigraphically controlled HiB-Li and LoB-Li deposits. As such, the primary directions of continuity for the mineralization are       horizontally within the preferentially mineralized B5, M5, S5 and L6 geological units.

	Criteria		JORC Code 2012 explanation		Commentary
			•       The factors affecting continuity both of grade and geology.		•    The primary factor affecting the continuity of both geology and grade is the lithology of the geological units. HiB-Li mineralization is favourably concentrated in marl-claystone of the B5 and L6 units and LoB-Li in the M5, S5 and L6 units. Mineralogy of the units also has a direct effect on the continuity of the mineralization, with elevated B grades in the B5 and M5 units associated with a distinct reduction in carbonate and clay content in the units, while higher Li values tend to be associated with elevated carbonate content in these units and sometimes k-felspar. •    Additional factors affecting the continuity of geology and grade include the spatial distribution and thickness of the host rocks which have been impacted by both syn-depositional and post- depositional geological processes (i.e. localized faulting, erosion and so forth).
	Dimensions		•          The extent and variability of the Mineral Resource expressed as length (along strike or otherwise), plan width, and depth below surface to the upper and lower limits of the Mineral Resource.		•     The Mineral Resource evaluation presented in this Report covers an area of approximately 458 Ha within the South Basin of Rhyolite Ridge. The Mineral Resource plan dimensions, defined by the spatial extent of the B5 unit Inferred classification limits, are approximately 3,650 m North-South by 1,400 m East-West. The upper and lower limits of the Mineral Resource span from surface, where the mineralized units outcrop locally, through to a maximum depth of 420 m below surface for the base of the lower mineralized zone (L6 unit). •     Variability of the Mineral Resource is associated primarily with the petrophysical and geochemical properties of the individual geological units in the Cave Spring Formation. These properties played a key role in determining units that were favourable for hosting HiB-Li and LoB-Li mineralization versus those that were not.

	Criteria		JORC Code 2012 explanation		Commentary
	Estimation and modelling techniques		•        The nature and appropriateness of the estimation  technique(s) applied and key assumptions, including treatment of extreme grade values, domaining, interpolation parameters and maximum distance of extrapolation from data points. If a computer assisted estimation method was chosen include a description of computer software and parameters used.		•     Geological modelling and Mineral Resource estimation for the Project was performed under the supervision of the Competent Person. •     Based on a statistical analysis, extreme B grade values were identified in some of the units other than the targeted B5, M5, S5 and L6 units.  Boron, Lithium and the other elements were estimated in only units B5, M5, S5 and L6. •     The geological model was developed as a gridded surface stratigraphic model by NewFields and ioneer and provided to IMC as surfaces and solids.  The stratigraphically constrained grade block model was developed using Hexagon and IMC software, which are computer-assisted geological, grade modelling, and estimation software applications. •     Domaining in the model was constrained by the roof and floor surfaces of the geological units. The unit boundaries were modelled as hard boundaries, with samples interpolated only within the unit in which they occurred.  The impact of faulting is represented in fault blocks which generated sub-sets of the seam units.  The faulting altered the orientation of the seam floors and was used during the grade estimation process.  Grade continuity is assumed across faults which in some cases offset the seams in a vertical direction.  A larger vertical window was used during grade estimation to allow estimation of grades across faults, still limited to the seam being estimated. •     Key modelling and estimation parameters included the following:
						Estimation Parameter		Description
						Estimation Block Size		7.62 x 7.62 x 1.524 m
						Estimation Method		Inverse Distance Squared
						Seams for Grade Estimation		M5, B5, S5, L6
						Maximum search distance, M5		259 x 259 x 30.5 m
						Maximum search distance, B5		533 x 305 x 30.5 m
						Maximum search distance, S5		229 x 229 x 30.5 m
						Maximum search distance, L6		305 x 305 x 30.5 m
						Minimum & Maximum samples		1 and 10
						Maximum samples per hole		3

	Criteria		JORC Code 2012 explanation		Commentary
			•     Any assumptions behind modelling of selective mining units.		•    Assumptions relating to selective mining units were based on the interpretation that the HiB-Li mineralization encountered is stratigraphically constrained and that mineralized and non- mineralized units can be selectively separated by existing mining and processing methods.
			•      Any assumptions about correlation between variables.		•      No assumptions or calculations relating to the correlation between variables were made at this time.
			•      Description of how the geological interpretation was used to control the resource estimates.		•    The geological interpretation was used to control the Mineral Resource estimate by developing a contiguous stratigraphic model (all units in the sequence were modelled) of the host rock units deposited within the basin, the roof and floor contacts of which then served as hard contacts for constraining the grade interpolation. Grade values were interpolated within the geological units using only samples intersected within those units.
			•      Discussion of basis for using or not using grade cutting or capping.		•    Grade capping or cutting was not applied for the targeted mineralized units B5, M5, S5 and L6 as a statistical analysis of the grade data indicated there was no bias or influence by extreme outlier grade values. •     Grades and Mineral Resources were not estimated for the other units.  Grades may be estimated for adjacent units to the targeted mineralized units at a later date to allow for potential mining dilution evaluations during later studies.
			•      The process of validation, the checking process used, the comparison of model data to drill hole data, and use of reconciliation data if available.		•    The geological model validation and review process involved visual inspection of drill hole data as compared to model geology and grade parameters using plan isopleth maps and approximately 300  m spaced cross-sections through the model. Drill hole and model values were compared statistically as well as via along-strike and down-dip swath plots.

	Criteria		JORC Code 2012 explanation		Commentary
					•     No reconciliation data is available because the property is not in production.
	Moisture		•     Whether the tonnages are estimated on a dry basis or with natural moisture, and the method of determination of the moisture content.		•    The estimated Mineral Resource tonnages are presented on a dry basis. •     A moisture content evaluation needs to be done as part of future analytical programs.
	Cut-off parameters		•     The basis of the adopted cut-off grade(s) or quality parameters applied.		•    The Mineral Resource estimate presented in this Report has been constrained by the application of an optimized Mineral Resource pit shell. The Mineral Resource pit shell was developed using the IMC Mine Planning software. •    The Mineral Resource estimate assumes the use of three processing streams: one which can process ore with boron content greater than 5,000 ppm and two which can process ore with boron content less than 5,000 ppm. •    Key input parameters and assumptions for the Mineral Resource pit shell included the following: •    B cut-off grade of 5,000 ppm for HiB-Li processing stream and no B cut-off grade for LoB-Li processing stream •    No Li cut-off grade for HiB-Li processing stream and Li cut-off grade of 1,090 ppm for LoB-Li processing stream •    Overall pit slope angle of 42 degrees (wall angle guidance provided by Geo-Logic Associates who developed the geotechnical design). •    Mining cost of US$1.54 /tonne based on recent studies by ioneer. •     Ore processing and grade control costs vary by process stream and seam unit and are divided into fixed cost and the cost of acid consumption.  Shown below are the costs based on the average grades of the acid consuming elements in the Mineral Resource: •    Stream 1 (HiB-Li): fixed process cost = $30.50/mt and acid costs range between $36.98/mt and $54.85/mt based on the average grades of the acid consuming elements in each seam. •    Streams 2 & 3 (LoB-Li): both the fixed and acid costs vary by seam with the fixed cost ranging between $15.19.mt to $30.80/mt and the acid costs range between $37.15/mt and %56.93/mt.

	Criteria		JORC Code 2012 explanation		Commentary
					•     Boron and Li recovery of 80.2% and 85.7% respectively for HiB-Li Processing Stream . •     Boron Recovery for LoB-Li Processing Stream variable by lithology as follows: 65% in M5 Unit, 80% in B5 unit, 50% in S5 unit, and 37% in L6 unit. •     Lithium Recovery for LoB-Li Processing Stream variable by lithology as follows: 78% in M5 unit, 88% in B5 unit, 88% in S5 unit, and 85% in L6 unit. •     Boric Acid sales price of US$1,016.67/tonne. •      Lithium Carbonate sales price of US$17,868.50/tonne. •     Sales/Transport costs are included in the process fixed cost/t.
	Mining factors or assumptions		•     Assumptions made regarding possible mining methods, minimum mining dimensions and internal (or, if applicable, external) mining dilution. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential mining methods, but the assumptions made regarding mining methods and parameters when estimating Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the mining assumptions made.		•   The Mineral Resource estimate presented in this Report was developed with the assumption that the HiB-Li and LoB-Li mineralization within the Mineral Resource pit shell, as described in the preceding section, has a reasonable prospect for eventual economic extraction using current conventional open pit mining methods. •    The basis of the mining assumptions made in establishing the reasonable prospects for eventual economic extraction of the HiB- Li mineralization are based on preliminary results from mine design and planning work that is in-progress as part of an ongoing Feasibility Study for the Project. •    Except for the Mineral Resource pit shell criteria discussed in the preceding section, no other mining factors, assumptions or mining parameters such as mining recovery, mining loss or dilution have been applied to the Mineral Resource estimate presented in this Report.
	Metallurgical factors or assumptions		•      The basis for assumptions or predictions regarding metallurgical amenability. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential metallurgical methods, but the assumptions regarding metallurgical treatment processes and parameters made when reporting Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the metallurgical assumptions made.		•   The basis of the metallurgical assumptions made in establishing the reasonable prospects for eventual economic extraction of the HiB-Li mineralization are based on results from metallurgical and material processing work that was developed as part of the ongoing Feasibility Study for the Project. This test work was performed using current processing and recovery methods for producing Boric acid and Lithium carbonate products •   A second process stream to recover Li from low boron mineralized (LoB-Li) units is being developed. Current results indicate a reasonable process and expectation for economic extraction of the LoB-Li from the S5, M5 and L6 units. This test work was  performed using current processing and recovery methods for producing Boric acid and Lithium carbonate products.

	Criteria		JORC Code 2012 explanation		Commentary
	Environment- al factors or assumptions		Assumptions made regarding possible waste and process residue disposal options. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider the potential environmental impacts of the mining and processing operation. While at this stage the determination of potential environmental impacts, particularly for a greenfields project, may not always be well advanced, the status of early consideration of these potential environmental impacts should be reported. Where these aspects have not been considered this should be reported with an explanation of the environmental assumptions made.		The project will require waste and process residue disposal. Assumptions have been made that all environmental requirements will be achieved through necessary studies, designs and permits. •    Currently, baseline studies and detailed designs have been completed for both waste and process residue disposal facilities. •     In December 2022, the United States Fish and Wildlife Service (USFWS) listed Tiehm’s buckwheat as an endangered species under the Endangered Species Act (ESA) and has designated critical habitat by way of applying a 500 m radius around several distinct plant populations that occur on the Project site. Ioneer is committed to the protection and conservation of the Tiehm’s buckwheat. The Project’s Mine Plan of Operations submitted to the BLM in July 2022 and currently under NEPA review has no direct impact on Tiehm’s buckwheat and includes measures to minimise and mitigate for indirect impacts within the designated critical habitat areas identified. •    The mineral resource pit shell used to constrain the April 2024, mineral resource estimate was not adjusted to account for any impacts from avoidance of Tiehm’s buckwheat or minimisation of disturbance within the designated critical habitat. Environmental and permitting assumptions and factors will be taken into consideration during future modifying factors studies for the Project. These permitting assumptions and factors may result in potential changes to the Mineral Resource footprint in the future.
	Bulk density		•   Whether assumed or determined. If assumed, the basis for the assumptions. If determined, the method used,  whether wet or dry, the frequency of the measurements, the nature, size and representativeness of the samples.		•     The density values used to convert volumes to tonnages were assigned on a by-geological unit basis using mean values calculated from 120 density samples collected from drill core during the 2018-2019 and the 2023-2024 drilling programs. The density analyses were performed using the water displacement method for density determination, with values reported in dry basis. •    The application of assigned densities by geological unit assumes that there will be minimal variability in density within each of the units across their spatial extents within the Project area. The use of assigned density with a very low number of samples, as is the case with several waste units, is a factor that increases the uncertainty and represents a risk to the Mineral Resource estimate confidence

Criteria		JORC Code 2012 explanation		Commentary
		•       The bulk density for bulk material must have been measured by methods that adequately account for void         spaces (vugs, porosity, etc.), moisture and differences between rock and alteration zones within the deposit.		• The Archimedes-principle method for density  determination accounts for void spaces, moisture and differences in rock type.
		•       Discuss assumptions for bulk density estimates used in the evaluation process of the different materials.		•    Density values were assigned for all geological units in the model, including mineralized units as well as overburden, interburden and underburden waste units. By-unit densities were assigned in the grade block model based on the block geological unit code as follows:

	Criteria		JORC Code 2012 explanation		Commentary
	Classification		The basis for the classification of the Mineral Resources into varying confidence categories.		•   The Mineral Resource estimate for the Project is reported here in accordance with the “Australian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves” as prepared by the Joint Ore Reserves Committee (the JORC Code, 2012 Edition). •    IMC performed a statistical and geostatistical analysis for the purpose of evaluating the confidence of continuity of the geological units and grade parameters. The results of this analysis were applied to developing the Mineral Resource classification criteria. •   Estimated Mineral Resources were classified as follows: •    Measured: Between 107 and 122 m spacing between points of observation depending on the seam, with sample interpolation from a minimum of four drill holes. •     Indicated: Between 168 and 198 m spacing between points of observation, with sample interpolation from a minimum of three drill holes. •     Inferred: To the limit of the estimation range (maximum 533 m, depending on the seam), with sample interpolation from a minimum of one drill hole.
			•     Whether appropriate account has been taken of all relevant factors (i.e. relative confidence in tonnage/grade estimations, reliability of input data, confidence in continuity of geology and metal values, quality, quantity and distribution of the data).		•    The Mineral Resource classification has included the consideration of data reliability, spatial distribution and abundance of data and continuity of geology and grade parameters

	Criteria		JORC Code 2012 explanation		Commentary
			•         Whether the result appropriately reflects the Competent Person’s view of the deposit.		•    It is the Competent Persons view that the classification criteria applied to the Mineral Resource estimate are appropriate for the reliability and spatial distribution of the base data and reflect the confidence of continuity of the modelled geology and grade parameters.
			The results of any audits or reviews of Mineral Resource estimates.		•     Beyond high level review for the purpose of understanding the Project history, no formal audits or reviews of previous or historical Mineral Resource estimates were performed as part of the scope of work; Mineral Resource estimation evaluation is limited to the estimate prepared by IMC and presented in this Report.
			•         Where appropriate a statement of the relative accuracy and confidence level in the Mineral Resource estimate using an approach or procedure deemed appropriate by the Competent Person. For example, the application of statistical or geostatistical procedures to quantify the relative accuracy of the resource within stated confidence limits, or, if such an approach is not deemed appropriate, a qualitative discussion of the factors that could affect the •          relative accuracy and confidence of the estimate.		•     IMC performed a statistical and geostatistical analysis and applied Mineral Resource classification criteria to reflect the relative confidence level of the estimated Mineral Resource tonnes and grades estimated globally across the model area for the Project.
	Audits or reviews		•        The statement should specify whether it relates to global or local estimates, and, if local, state the relevant tonnages, which should be relevant to technical and economic evaluation. Documentation should include assumptions •          made and the procedures used.		•     The Mineral Resource tonnes and grade have been estimated globally across the model area for the Project.
	Discussion of relative accuracy/ confidence		These statements of relative accuracy and confidence of the estimate should be compared with production data, where available.		•     Reconciliation against production data/results was not possible as the Project is currently in the development stage and there has been no production on the Project to date.