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PMET Demonstrates >97% Caesium Extraction from Pollucite Concentrate Multiple pathways to value-add caesium chemicals identified during b ench-scale extraction testwork at SGS Lakefield and through Koch Technology Solutions Phase 1 program

Corporate Updates

PMET Resources Inc.

Suite 900 - 1801 McGill College, Montreal, Qc, Canada, H3A 1Z4

www.pmet.ca / TSX: PMET / ASX: PMT / OTC: PMETF / FSE: R9GA

PMET Demonstrates >97% Caesium Extraction from Pollucite

Concentrate

Multiple pathways to value-add caesium chemicals identified during b ench-scale extraction testwork at

SGS Lakefield and through Koch Technology Solutions Phase 1 program

July 12, 2026 – Montreal, QC, Canada July 13, 2026 – Sydney, Australia

HIGHLIGHTS

SGS CANADA CAESIUM EXTRACTION TEST PROGRAM

• Leaching of pollucite concentrate using sulphuric acid was highly successful with

>97% recovery of the caesium (Cs) into solution achieved.

• Bench-scale testwork on impurity removal was also successful, demonstrating

efficient removal of key impurities such as aluminum.

• Opportunity identified to potentially recover a rubidium by-product.

• Primary objective of program was fully realized – that being to identify a preliminary

set of conditions to extract caesium from pollucite concentrate (produced from the Vega

Zone) at high recovery while characterizing (and limiting) the impurity profile.

• Next steps will build upon this extraction phase of work with a primary objective to

produce gram quantities of high-purity Cs-sulphate, Cs-carbonate, Cs-formate,

and potentially Rb-carbonate.

KOCH TECHNOLOGY SOLUTIONS CAESIUM EXTRACTION TEST PROGRAM

• PMET is working with Koch Technology Solutions, part of Koch Inc., evaluating advanced

processing pathways to value-added caesium products.

• Preliminary results from Phase 1 indicate both synthetic and live Pregnant Leaching

Solution yield very selective high loading factors of c aesium recovery using

Koch’s proprietary flow sheet.

PMET RESOURCES INC. (THE “COMPANY” OR “PMET”) (TSX: PMET) (ASX: PMT)

(OTCQX: PMETF) (FSE: R9GA is pleased to provide an update on two parallel bench-scale

testwork programs focused on caesium (Cs) extraction from pollucite samples fro m the

Shaakichiuwaanaan Project. Both approaches – conventional by SGS Canada, and proprietary by

Koch Technology Solutions – offer attractive process routes for caesium extraction from

pollucite concentrate into marketable chemical products. The Company is motivated to consider

caesium value-added chemical production (with key partners) to unlock maximum value from its

globally significant caesium resource and its pollucite concentrates produced at site.

In addition to being one of the largest lithium-tantalum pegmatite Mineral Resources1 and lithium

pegmatite Mineral Reserves2 globally, the Property also hosts the world’s largest in-situ pollucite-

hosted caesium pegmatite Mineral Resource, comprising 0.69 Mt at 4.40% Cs2O (Indicated) and

1.70 Mt at 2.40% Cs2O (Inferred). The CV13 Pegmatite, host to the caesium Mineral Resource,

is located <3 km along trend from the CV5 Pegmatite, which is situated approximately 13 km

south of the regional Trans -Taiga Road and powerline infrastructure corridor, and is accessible

year-round by road.

The pollucite concentrate used as feed for both extraction testwork programs ( Figure 1, top)

was produced by X -Ray Transmission (XRT) ore sorting of drill core material from the Vega

Caesium Zone at the CV13 Pegmatite (see news release dated October 9, 2025) and assayed

12% Cs2O (Figure 2).

SGS Canada Caesium Extraction Testwork Program

At SGS Lakefield, a conventual process approach (Figure 1, bottom) for caesium extraction from

pollucite concentrate is being advanced using sulphuric acid digestion (H 2SO4) and subsequent

impurity removal. The primary objective of this initia l bench-scale test program is to identify a

preliminary set of conditions to extract caesium at high recovery while characterizing (and

limiting) the impurity profile.

The pollucite concentrate sample (~15 kg) was ground to varying sizes (P80 of 75 µm to 212 µm)

and a portion (<4 kg) subjected to sulphuric acid (H 2SO4) leaching at varying temperatures (up

to 120°C). The program was highly successful with the testwork achieving consistently high

extractions of 97- 98% Cs while maintaining significantly lower extractions of key

impurities (e.g., Al). Further, s ubsequent impurity tests successfully removed the remaining

aluminum (Al) and a majority of the sulphur (S) with negligible caesium (Cs) losses.

Additionally, the program also identified a potential opportunity to recover a rubidium by-

product from one of the waste streams . Further characterization of this opportunity was not

undertaken during this initial bench-scale caesium extraction test phase and will be investigated

as a secondary objective in future work.

The testwork was completed at SGS Canada ’s Lakefield, Ontario , facility with support from

Primero Group Americas and a Company-retained Subject Matter Expert ("SME") specializing in

caesium extraction and recovery from pollucite. These three parties, in addition to TOMRA

Mining, are also key contributors to the design and execution of the Company’s ore sorting

programs.

1 Consolidated MRE (CV5 + CV13 pegmatites) totals 108.0 Mt at 1.40% Li 2O and 166 ppm Ta 2O5 (Indicated), and 33.4 Mt at 1.33%

Li2O and 155 ppm Ta 2O5 (Inferred), at an Li 2O cut-off grade of 0.40% (open -pit), 0.60% (underground CV5), and 0.70% (underground

CV13). A grade constraint of 0.50% Cs 2O was used to model the Rigel and Vega caesium zones, contained entirely within CV13, with a

MRE of 0.69 Mt at 4.40% Cs2O (Indicated), and 1.70 Mt at 2.40% Cs2O (Inferred). The Effective Date is June 20, 2025. Mineral Resources

are not Mineral Reserves as they do not have demonstrated economic viability. Mineral Resources are inclusive of Mineral Reserves.

2 Probable Mineral Reserve of 84.3 Mt at 1.26% Li2O at the CV5 Pegmatite with a cut-off grade is 0.40% Li2O (open-pit) and 0.70% Li2O

(underground). Underground development and open -pit marginal tonnage containing material above 0.37% Li 2O are also included in the

statement. The Effective Date is September 11, 2025. See Feasibility Study news release dated October 20, 2025.

Figure 1: Simplified conceptual flowsheet for conventional processing of pollucite pegmatite through to

pollucite concentrate (top) and from pollucite concentrate to final marketable caesium salts/brine

(bottom). The bench-scale testwork carried out by SGS Canada is focused on the caesium extraction and

impurity removal steps. The stated >97% Cs recovery is with respect to the pollucite concentrate feed

through to initial impurity removal.

Figure 2: Pollucite concentrate (~12% Cs 2O) produced from prior XRT ore sorting program (see news

release dated October 9, 2025) , of which a portion was used as feed for the bench- scale caesium

extraction and recovery program at SGS Canada and Koch Technology Solutions discussed herein.

Next steps will build upon this bench- scale testwork with a primary “proof -of-concept”

objective to produce gram quantit y samples of high -purity Cs -sulphate, Cs -

carbonate, Cs -formate, and potentially Rb -carbonate. This test program is currently

underway at SGS Canada’s facility in Lakefield, Ontario, with results expected circa Q4 2026.

Koch Technology Solutions Caesium Extraction Testwork Program

The testwork program with Koch Technology Solutions ( “KTS”) has been developed as part of

a strategic relationship that has evolved following the Company’s investigations of the caesium

industry, commercial engagement, and research. The program will leverage KTS’s demonstrated

capabilities in engineering, development and commercialization of critical minerals extraction

technologies to produce a range of value-added caesium chemical compounds.

The bench-scale test program being advanced by KTS is designed to assess the application of their

proprietary flowsheet technology , to produce a range of value -added caesium chemical

compounds. Approximately 6 kg of pollucite concentrate is being used to support the testwork.

Preliminary results from Phase 1 of the program indicate a strong and selective

caesium recovery. The testwork will now move onto Phase 2 and the Company anticipates

expanding the mandate to produce gram quantities of caesium derivative products as a complete

bench-scale proof-of-concept.

STUDY WORK UNDERWAY

A Preliminary Economic Assessment ("PEA") for the broader Project, incorporating lithium,

caesium, and tantalum, is scheduled for completion in Q4 2026. The PEA will complement the

Feasibility Study for the CV5 Pegmatite (lithium and tantalum), which is also scheduled for

completion in Q4 2026, and will provide the first economic assessment of the Project's caesium

potential.

ABOUT KOCH TECHNOLOGY SOLUTIONS.

Koch Technology Solutions (KTS) is a global leader in technology development,

commercialization and licensing. KTS works with owners, developers, and investors in the

process manufacturing and critical minerals sectors to solve complex technical and invest ment

challenges before large capital is committed, helping clients make confident decisions from early

concept through EPC-ready design. With a global network and rich history of domain experience

and expertise, KTS gains additional strength from its position within Koch Engineered Solutions

(KES). This backing enhances our ability to partner with companies developing chemical process

technologies, create attractive licensing solutions for commercial deployment, and bring the next

generation of technologies to the market.

For further information, please contact us at [email protected] or by calling +1 (604) 279- 8709, or

visit www.pmet.ca. Please also refer to the Company’s continuous disclosure filings, available

under its profile at www.sedarplus.ca and www.asx.com.au, for available exploration data.

QUALIFIED/COMPETENT PERSON

The technical and scientific information in this news release that relates to the Mineral Resource

Estimate, exploration, and metallurgical results for the Company’s properties is based on, and

fairly represents, information compiled by Mr. Darren L. Smith, M.Sc., P.Geo., who is a Qualified

Person as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI

43-101”), and member in good standing with the Ordre des Géologues du Québec (Geologist Permit

number 01968), and with the Association of Professional Engineers and Geoscientists of Alberta

(member number 87868). Mr. Smith has reviewed and approved the related technical information

in this news release.

Mr. Smith is an Executive and Vice President of Exploration for PMET Resources Inc. and holds

common shares, Restricted Share Units (RSUs), Performance Share Units (PSUs), and options in

the Company.

Mr. Smith has sufficient experience, which is relevant to the style of mineralization, type of deposit

under consideration, and to the activities being undertaken to qualify as a Competent Person as

described by the Australasian Code for Reporting of Exploration Results, Mineral Resources and

Ore Reserves (the JORC Code). Mr. Smith consents to the inclusion in this news release of the

matters based on his information in the form and context in which it appears.

The information in this news release that relates to the Mineral Reserve Estimate and Feasibility

Study is based on, and fairly represents, information compiled by Mr. Frédéric Mercier-Langevin,

Ing. M.Sc., who is a Qualified Person as defined by NI 43-101, and member in good standing with

the Ordre des Ingénieurs du Québec. Mr. Mercier -Langevin has reviewed and approved the

related technical information in this news release.

Mr. Mercier-Langevin is the Chief Operating and Development Officer for PMET Resources Inc.

and holds common shares, RSUs, PSUs, and options in the Company.

ABOUT PMET RESOURCES INC.

PMET Resources Inc. is a pegmatite critical mineral exploration and development company

focused on advancing its district -scale 100%-owned Shaakichiuwaanaan Property located in the

Eeyou Istchee James Bay region of Quebec, Canada, which is accessible year-round by all-season

road and proximal to regional hydro-power infrastructure.

In late 2025, the Company announced a positive lithium -only Feasibility Study on the CV5

Pegmatite for the Shaakichiuwaanaan Property and declared a maiden Mineral Reserve of 84.3 Mt

at 1.26% Li 2O (Probable) 3. The study outlines the potential for a competitive and globally

significant high-grade lithium project targeting up to ~800 ktpa spodumene concentrate using a

simple Dense Media Separation (“DMS”) only process flowsheet. Further, the results highlight

Shaakichiuwaanaan as a potential North American critical mineral powerhouse with significant

opportunity for tantalum and caesium in addition to lithium.

The Project hosts a Consolidated Mineral Resource 4 totalling 108.0 Mt at 1.40% Li 2O and 166

ppm Ta2O5 (Indicated) and 33.4 Mt at 1.33% Li 2O and 155 ppm Ta2O5 (Inferred), and ranks as a

top ten lithium pegmatite globally in size. Additionally, the Project hosts the world’s

largest pollucite-hosted caesium pegmatite Mineral Resource at the Rigel and Vega zones with

0.69 Mt at 4.40% Cs2O (Indicated), and 1.70 Mt at 2.40% Cs2O (Inferred).

3 See Feasibility Study news release dated October 20, 2025. Probable Mineral Reserve cut-off grade is 0.40% Li2O (open-pit) and 0.70%

Li2O (underground). Underground development and open -pit marginal tonnage containing material above 0.37% Li 2O are also included in

the statement. Effective Date of September 11, 2025.

4 Consolidated MRE (CV5 + CV13 pegmatites) is reported at an Li2O cut-off grade of 0.40% (open -pit), 0.60% (underground CV5), and

0.70% (underground CV13). A grade constraint of 0.50% Cs 2O was used to model the Rigel and Vega caesium zones, contained entirely

within CV13. The Effective Date is June 20, 2025. Mineral Resources are not Mineral Reserves as they do not have demonstrated economic

viability. Mineral Resources are inclusive of Mineral Reserves.

This news release has been approved by

“KEN BRINSDEN”

Kenneth Brinsden, President, CEO, & Managing Director

Olivier Caza-Lapointe

Head, Investor Relations

T: +1 (514) 913-5264

E: [email protected]

DISCLAIMER FOR FORWARD-LOOKING INFORMATION

This news release contains “forward -looking statements” and “forward -looking information”

within the meaning of applicable securities laws.

All statements, other than statements of present or historical facts, are forward -looking

statements. Forward -looking statements involve known and unknown risks, uncertainties and

assumptions and accordingly, actual results could differ materially from tho se expressed or

implied in such statements. You are hence cautioned not to place undue reliance on forward-

looking statements. Forward-looking statements are typically identified by words or expressions

such as “pathways”, “opportunity”, “potentially”, “objective”, “preliminary”, “conditions”, “next

steps”, “build upon”, “marketable, “to consider”, “to unlock”, “being advanced”, “scheduled, or

variations of such words or expressions and phrases or statements that certain actions, events

or results “may”, “could”, “would”, “might” or “will” be taken, occur or be achieved.

Forward-looking statements include, but are not limited to, statements concerning SGS Canada

and KTS Caesium Extraction Test Program, the schedule for the PEA and Feasibility Study for

the CV5 Pegmatite and the economics of caesium.

Forward-looking statements are based upon certain assumptions and other important factors

that, if untrue, could cause actual results to be materially different from future results expressed

or implied by such statements. There can be no assurance that for ward-looking statements will

prove to be accurate. Key assumptions upon which the Company’s forward-looking information

is based include, without limitation, the ability to obtain the required financing to bring the project

to development, the ability to make discoveries, the potential of each of tantalum, lithium and

caesium , that proposed exploration work on the Property and the results therefrom will

continue as expected, the accuracy of reserve and resource estimates, the classification of

resources and the assumptions on which the reserve and resource estimates a re based, long -

term demand for lithium (spodumene), tantalum (tantalite), and caesium (pollucite) supply, and

that exploration and development results continue to support management’s current plans for

the Property’s development.

Forward-looking statements are also subject to risks and uncertainties facing the Company’s

business, any of which could have a material adverse effect on the Company’s business, financial

condition, results of operations and growth prospects. Readers should review the detailed risk

discussion in the Company’s most recent Annual Information Form filed on SEDAR+, for a fuller

understanding of the risks and uncertainties that affect the Company’s business and operations.

Although the Company believes its expectations are based upon reasonable assumptions and has

attempted to identify important factors that could cause actual actions, events or results to differ

materially from those described in forward-looking statements, there may be other factors that

cause actions, events or results not to be as anticipated, estimated or intended. There can be no

assurance that forward- looking information will prove to be accurate. If any of the risks or

uncertainties mentioned above, which are not exhaustive, materialize, actual results may vary

materially from those anticipated in the forward-looking statements.

The forward- looking statements contained herein are made only as of the date hereof. The

Company disclaims any intention or obligation to update or revise any forward- looking

statements, whether as a result of new information, future events or otherwise, except to the

extent required by applicable law. The Company qualifies all of its forward-looking statements by

these cautionary statements.

COMPETENT PERSON STATEMENT (ASX LISTING RULES)

The information in this news release that relates to the Feasibility Study (“FS”) for the

Shaakichiuwaanaan Project, which was first reported by the Company in a market announcement

titled “ PMET Resources Delivers Positive CV5 Lithium -Only Feasibility Study for its Large-Scale

Shaakichiuwaanaan Project” dated October 20, 2025 (Montreal time) is available on the Company’s

website at www.pmet.ca , on SEDAR+ at www.sedarplus.ca and on the ASX website at

www.asx.com.au. The production target from the Feasibility Study referred to in this news

release was reported by the Company in accordance with ASX Listing Rule 5.16 on the date of

the original announcement. The Company confirms that, as of the date of this news releas e, all

material assumptions and technical parameters underpinning the production target in the original

announcement continue to apply and have not materially changed.

The Mineral Resource and Mineral Reserve Estimates in this release were first reported by the

Company in accordance with ASX Listing Rule s 5.8 and 5.9 in market announcements titled

"World's Largest Pollucite- Hosted Caesium Pegmatite Deposit " dated July 20, 2025 (Montreal time)

and “ PMET Resources Delivers Positive CV5 Lithium -Only Feasibility Study for its Large-Scale

Shaakichiuwaanaan Project ” dated October 20, 2025 (Montreal time) and are available on the

Company’s website at www.pmet.ca, on SEDAR+ at www.sedarplus.ca and on the ASX website

at www.asx.com.au. The Company confirms that, as of the date of this news release, it is not

aware of any new information or data verified by the competent person that materially affects

the information included in the relevant announcement and that all material assumptions and

technical parameters underpinning the estimates in the relevant announcement continue to apply

and have not materially changed. The Company confirms that, as at the date of this

announcement, the form and context in which the competent person’s findings are presented

have not been materially modified from the original market announcement.

APPENDIX 1 – JORC CODE 2012 TABLE 1 (ASX LISTING RULE 5.8.2)

Section 1 – Sampling Techniques and Data

Criteria JORC Code explanation Commentary

Sampling techniques • Nature and quality of sampling (eg cut • Pollucite concentrate, assaying ~12% Cs 2O, was used

Criteria JORC Code explanation Commentary

channels, random chips, or specific

specialized industry standard

measurement tools appropriate to the

minerals under investigation, such as

down hole gamma sondes, or handheld

XRF instruments, etc). These examples

should not be taken as limiting the

broad meaning of sampling.

• Include reference to measures taken to

ensure sample representivity and the

appropriate calibration of any

measurement tools or systems used.

• Aspects of the determination of

mineralization that are Material to the

Public Report.

• In cases where ‘industry standard’

work has been done this would be

relatively simple (eg ‘reverse

circulation drilling was used to obtain 1

m samples from which 3 kg was

pulverized to produce a 30 g charge for

fire assay’). In other cases more

explanation may be required, such as

where there is coarse gold that has

inherent sampling problems. Unusual

commodities or mineralization types

(eg submarine nodules) may warrant

disclosure of detailed information.

as feed to the bench-scale caesium extraction test

programs discussed herein. This pollucite concentrate

was produced using XRT ore sorting on NQ-sized drill

core (half -core) collected from the Vega Caesium

Zone as described in news release dated October 9,

2025.

Drilling techniques • Drill type (eg core, reverse circulation,

open-hole hammer, rotary air blast,

auger, Bangka, sonic, etc) and details

(eg core diameter, triple or standard

tube, depth of diamond tails, face -

sampling bit or other type, whether

core is oriented and if so, by what

method, etc).

• N/A. No drill results reported.

Drill sample

recovery

• Method of recording and assessing

core and chip sample recoveries and

results assessed.

• Measures taken to maximize sample

recovery and ensure representative

nature of the samples.

• Whether a relationship exists between

sample recovery and grade and

whether sample bias may have

occurred due to preferential loss/gain

• N/A. No drill results reported.