Lion at a Glance

~406Mlb contained CuEq | ~3.9% CuEq | >85% Indicated | Starts at surface |~59% of tonnes within open-pit resource | >98% Cu recovery | 25%+ Cu concentrate | MRE cut-off April 19| 5 rigs active| Post cut-off deep drilling not included | Assays expected by end of September

TORONTO, Sept. 8, 2026 /PRNewswire/ -- Power Metallic Mines Inc. (the "Company" or "Power Metallic") (TSXV: PNPN) (OTCBB: PNPNF) (Frankfurt: IVV1) is pleased to announce an updated Mineral Resource Estimate ("MRE") for its Nisk Project (Power Metallic 80% / Critical Elements Lithium Corp. 20%) in the Eeyou Istchee James Bay territory of Québec, including the inaugural mineral resource for the Lion Zone and an updated mineral resource for the Nisk Main deposit. The MRE was prepared by SGS Canada Inc. ("SGS") in accordance with National Instrument 43-101 – Standards of Disclosure for Mineral Projects ("NI 43-101") and the CIM Definition Standards for Mineral Resources and Mineral Reserves (2014), has an effective date of June 19, 2026, and incorporates drilling completed to April 19, 2026.

Power Metallic has declared the inaugural Mineral Resource Estimate for the Lion Zone, a high-grade, copper-dominant polymetallic deposit discovered in 2023 at the Nisk property. Over 85% of the initial Lion resource is classified as Indicated, while mineralisation remains open for expansion.

Lion contains 4,145,000 Mt Indicated at 3.86% CuEq (1.68% Cu, 2.61 g/t Pd, 0.85 g/t Pt, 0.49 g/t Au, 12.21 g/t Ag, 0.10% Ni), and 601,000 Mt Inferred at 4.01% CuEq (1.84% Cu, 2.86 g/t Pd, 0.59 g/t Pt, 0.41 g/t Au, 12.47 g/t Ag, 0.13% Ni).

Locked-cycle testing completed by SGS Canada of representative mineralization from Lion has returned copper recoveries above 98% across all composite samples tested, producing concentrates grading over 25% Cu, with high recoveries also reported for gold, palladium, platinum and silver.

The Company is currently assessing proposals from engineering firms to complete a Preliminary Economic Assessment ("PEA") evaluating the development potential of Lion including the integration of the Nisk resource.

Ongoing resource expansion drilling with 5 active rigs is targeting extensions at depth and along strike with assays from the summer 2026 program expected starting in September 2026.

The updated MRE also restates the existing Nisk nickel-copper resource, which will be assessed alongside Lion as part of the broader PEA development strategy.

Mineral Resource Statement

2026 Lion Deposit Mineral Resource Estimate at a cut-off grade of 0.35% CuEq for the open pit MRE and 0.90% CuEq for the underground MRE, June 19, 2026.

2026 Nisk Deposit Mineral Resource Estimate at a cut-off grade of 0.30% NiEq for the open pit MRE and 0.80% NiEq for the underground MRE, June 19, 2026.

Terry Lynch, CEO of Power Metallic, commented:
" This inaugural Lion resource confirms what the drilling has been telling us: Lion is a high-grade polymetallic deposit. Approximately 4.75 million tonnes grading close to 4% CuEq has been defined, containing approximately 406 million pounds of CuEq, with more than 85% of the resource already in the Indicated category. Importantly, high-grade mineralisation begins at surface, and the deposit remains open at depth. We believe the quality of Lion has been demonstrated. Now our focus is on demonstrating its scale.

The Federal and Québec governments have put a number of incentive programs in place for critical-minerals projects, and we believe the Company may qualify for several of them. Combining these potential incentives with the high-grade mineralisation from surface and our location next to existing road and major power infrastructure, Lion has the potential to be developed with a relatively modest initial footprint and capital requirement.

From here, the exploration question is how deep Lion goes and where the nickel went. Lion carries the copper and precious metals that come out of a magmatic sulphide system last; the nickel-rich sulphide that comes out first should be somewhere in the system, and we have not found it yet. The summer program has been aimed at the down-dip extension of the shoot, with some holes targeting hundreds of metres below the current resource. Assays on Lion Deep are expected by the end of September"

Joe Campbell, VP Exploration of Power Metallic, added:
"Lion is a textbook fractionated copper- and precious-metal-rich shoot within a magmatic sulphide system. The advantage at Lion over similar deposits of this type is that it begins at surface and is modelled continuously to more than 600 metres vertical depth. The deposit remains open at depth and our priority since the April 19, 2026 cut-off date for drill holes in the MRE has been to test the shoot below 600 metres with deep step-out drilling, following up with borehole EM to delineate more mineralization."

Lion Zone Geology and Depth Potential

The Lion Zone comprises multiple modelled lenses of copper–PGE–gold–silver–nickel–cobalt sulphide mineralization that together form a continuous, steeply plunging shoot extending from surface to approximately 675 metres down-dip (more than 600 metres vertical depth), the limit of drilling included in the MRE to April 19, 2026. The modelled shoot is approximately 400 metres along strike at its widest and 290 metres at its narrowest, and consists of multiple subparallel lenses, each approximately 2 to 15 metres thick, within a mineralized package up to 50 metres thick that dips at approximately 65° to the north-northwest. The high-grade core of the shoot is dominated by massive to brecciated chalcopyrite and cubanite with pyrrhotite, pentlandite and pyrite. The deepest reported hole intersecting the core of the Lion shoot to date (PML-25-002) intersected 1.95 metres at 7.95% CuEqRec* at approximately 610 metres vertical depth (see news release dated April 30, 2025). The Deposit remains open at depth with subsequent deeper drilling, as illustrated by drill targets PML26-121A, PML-26-125 and PML-26-128A in Figure 1, completed after the cut-off date for the MRE and below the modelled zone intersecting visible copper mineralization (assays pending).

Lion is interpreted as a magmatic sulphide system. As the sulphide liquid cools, nickel-rich monosulphide solid solution crystallizes first and the residual liquid becomes progressively enriched in copper, platinum, palladium, gold and silver. This fractionated, copper- and precious-metal-rich liquid is the most mobile phase and migrates furthest away, from the original source; the copper–PGE footwall vein deposits of the Sudbury district are the classic example. Lion's metal endowment – dominated by copper, palladium, platinum, gold and silver with subordinate nickel and cobalt, and with the highest palladium grades hosted in massive copper sulphide – is consistent with that fractionated end-member. The Company's working model is that the Lion shoot represents a gravity-driven sulphide accumulation whose down-plunge extent has not yet been tested.

Depth continuity of this order is well documented in analogous camps. In the Sudbury district, the Creighton mine has been developed to approximately 2.4 kilometres below surface; Glencore's Onaping Depth project has reached ore at approximately 2,600 metres; Nickel Rim South was mined between approximately 1,100 and 1,720 metres; and the copper–PGE footwall veins of the Morrison deposit at Levack were developed between approximately 1,200 and 1,650 metres and remain open at depth. Readers are cautioned that the depth extent and grade of mineralization at these deposits are not necessarily indicative of the mineralization at Lion, which has been drilled to approximately 600 metres vertical depth (see "Cautionary Notes" below).

Power Metallic's program to test the down-plunge extension of the Lion shoot includes borehole electromagnetic surveys from the deepest holes on the shoot, and deep step-out and wedge drilling from existing collars. Results will be incorporated into future resource updates.

Metallurgy

Metallurgical test work on Lion mineralization has been carried out by SGS at its Quebec City and Lakefield laboratories (see news releases dated January 19, 2026 and May 26, 2026). Two locked-cycle flotation tests have been completed: LCT1, on a blended composite of high-grade and low-grade material representative of run-of-mine feed, and LG2, on a low-grade composite of disseminated mineralization designed to test whether lower-grade material responds to conventional flotation. Both tests produced a single high-grade copper concentrate carrying the platinum, palladium, gold, silver and nickel, with results summarized in Table 4. The LG2 results support the inclusion of lower-grade disseminated material in the Mineral Resource. Mineralogical work indicates that copper occurs as coarse-grained chalcopyrite and cubanite and that most platinum-group minerals occur within or attached to those copper sulphides (see news release dated July 23, 2025). Hydrometallurgical testing of the copper concentrate to evaluate a direct-to-metal processing route is in progress. The metallurgical recoveries applied in the MRE are set out in Note 7 to Table 1.

These metallurgical results are analogous to similar deposits in the Sudbury camp noted above and typical of the high-grade Cuprous zone or Copper zone of these deposits.

Table 4: Lion Zone locked-cycle flotation test results (SGS Canada Inc.)

Location and Infrastructure

The Nisk Project is in the Eeyou Istchee James Bay territory of Québec, approximately 280 kilometres north-northwest of Chibougamau and 425 kilometres northeast of Matagami. The property is accessed by the Route du Nord, an all-season road managed by the Société de développement de la Baie-James that connects Route 167 at Chibougamau to the paved Billy-Diamond Highway Hydro-Québec's Albanel substation, on the 735 kV transmission system that carries power from the La Grande complex to southern Québec and accessed by the Route du Norde, is located adjacent to the property approximately 4 km from the Nisk Main deposit and 9.1 km from the Lion Zone. The Nemiscau airport (1,524 metre gravel runway, with scheduled service by Air Creebec) is approximately 30 kilometres west of the property along the Route du Nord, and the Nemiscau camp on the Route du Nord, operated by the Cree Construction and Development Company, provides lodging, food services and fuel. The Cree community of Nemaska, approximately 51 kilometres by road, has a hotel and restaurant, grocery, fuel, a health clinic and other services available to Project staff.

Regional transportation and energy infrastructure in Eeyou Istchee James Bay continues to be upgraded. The Société de développement de la Baie-James is carrying out a multi-year rehabilitation of the Billy-Diamond Highway, the 2026–2027 Québec budget allocated a further $19.4 million over two years to the maintenance of that highway, and in 2025 the Société du Plan Nord and Nemaska Lithium co-funded a $9.2 million upgrade of the Matagami rail transshipment yard, which serves mining projects in the region. Québec's 2025–2031 Critical and Strategic Minerals Strategy, released in January 2026, includes a commitment to develop an infrastructure development plan for the Eeyou Istchee James Bay region, and the feasibility studies completed in 2024 under the La Grande Alliance between the Cree Nation Government and the Government of Québec examined a potential rail line from Matagami along the Billy-Diamond Highway and an upgrade of the Route du Nord. Under Québec's 2025 energy legislation, industrial power allocations of 5 MW or more require ministerial authorization, and the Government of Québec has indicated that critical and strategic minerals projects are a priority for such allocations.

Critical Minerals and Government Incentives

Copper, platinum, palladium, nickel and cobalt are each included on the critical minerals lists of Québec, Canada, the United States and the European Union, and silver is also included on the United States list (Table 6).

Table 6: Nisk Project metals on government critical minerals lists

Canada's Clean Technology Manufacturing investment tax credit ("CTM ITC") provides a refundable tax credit equal to 30% of the capital cost of eligible new machinery and equipment used in the extraction and processing of qualifying critical minerals, including copper, nickel and cobalt, for property that becomes available for use by the end of 2031. Amendments enacted in March 2026 extended eligibility to mine-site extraction and processing property where 50% or more of the expected value of the commercial output is attributable to qualifying materials, subject to certification by an independent engineer or geoscientist. Copper is expected to be the largest contributor to the Project's anticipated output value, and nickel and cobalt are also qualifying materials; on that basis the Company believes the Project is well positioned to satisfy the eligibility test and is evaluating the application of the credit to a future development of the Project. The principal federal and Québec measures the Company is evaluating are summarized in Table 7.

Table 7: Principal federal and Québec critical-minerals tax credits and incentive programs under evaluation

Power Metallic is evaluating the relevance of each of these programs to the Project and believes the Project qualifies for several of them. Eligibility for any program is subject to the applicable legislation, regulations and administrative determinations, and no assurance can be given that the Project will qualify for or receive any tax credit or incentive.

Next Steps

The MRE forms the basis for a Preliminary Economic Assessment (PEA). The PEA will evaluate an initial open pit followed by underground mining at Lion with processing options including the potential incorporation of Nisk Main feed. Additional work is being carried out on improving Nisk metallurgical recovery while preserving an efficient pathway to Lion development. Drilling completed since the MRE data cut-off (five rigs are currently active across the Nisk land package), with results expected from September 2026 onward, will be incorporated into future resource updates and into the PEA to the extent practicable.

A two-year environmental baseline survey program commenced in January 2026, following completion of a desktop study in April 2025. The first field season is being conducted from May to October 2026, with a second planned for summer 2027. To support completion within the planned two-year timeframe, the program has been designed to cover a broader area than is currently expected to be required, including a conservatively defined area for hydrological surveys. Its scope will continue to be reviewed as survey results are received and the project design evolves. The currently defined program is scheduled for completion in 2027 and is progressing in parallel with the technical studies to support preparation of the Environmental and Social Impact Assessment.

A technical report prepared in accordance with NI 43-101 in support of the MRE will be filed under the Company's profile on SEDAR+ at www.sedarplus.ca within 45 days of the date of this news release.

With the updated Technical Report, Power Metallic will be able to submit the last requirement in its Nasdaq application process. The Company is applying for an American Depositary Receipt (ADR) on Nasdaq. This would enable Power Metallic to trade on Nasdaq via a multiple of its shares to meet the Nasdaq $4 threshold. The Company would expect to advise on its Nasdaq application in October.

6ix Presentation

Power Metallic will be hosting a webinar on Tuesday September 8th, 2026, at 12 noon (Eastern). It will be recorded for those who cannot attend. The link below will provide details how to attend the live event.

https://6ix.com/event/power-metallic-mineral-resource-estimate-presentation

Qualified Persons

Marc-Antoine Laporte, P.Geo., of SGS Canada Inc., is the independent Qualified Person responsible for the MRE, as defined by NI 43-101, and has reviewed and approved the scientific and technical disclosure relating to the MRE in this news release. Joseph Campbell, P.Geo., VP Exploration of Power Metallic, is a Qualified Person as defined by NI 43-101 and has reviewed and approved the other scientific and technical information in this news release.

Cautionary Notes

Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. The Company has not completed a PEA or any other economic study of the Nisk Project. The mining concepts described in this news release were used solely to establish reasonable prospects for eventual economic extraction for the purpose of reporting Mineral Resources; they do not constitute a mine plan or an economic analysis, and the mining sequence, production rate and mine life of any future operation have not been determined. This news release refers to other mineral deposits and mines, including in the Sudbury and Norilsk–Talnakh districts, solely to illustrate the depths to which magmatic sulphide mineralization has been mined elsewhere. The Company has no interest in those properties, and the mineralization on those properties is not necessarily indicative of the mineralization at the Nisk Project.

About Power Metallic Mines Inc.

Power Metallic is a Canadian exploration company focused on advancing the Nisk Project Area (Nisk–Lion–Tiger)—a high–grade Copper–PGE, Nickel, gold and silver system—toward Canada's next polymetallic mine.

On 1 February 2021, Power Metallic (then Chilean Metals) secured an option to earn up to 80% of the Nisk project from Critical Elements Lithium Corp. (TSX–V: CRE). Following the June 2025 purchase of 313 adjoining claims (~167 km²) from Li–FT Power, the Company now controls ~330 km² and roughly 50 km of prospective basin margins.

Power Metallic is expanding mineralization at the Nisk and Lion discovery zones, evaluating the Tiger target, and exploring the enlarged land package through successive drill programs. Beyond the Nisk Project Area, Power Metallic indirectly has an interest in significant land packages in British Columbia and Chile, by its 50% share ownership position in Chilean Metals Inc., which were spun out from Power Metallic via a plan of arrangement on February 3, 2025.

It also owns 100% of Power Metallic Arabia which owns 100% interest in the Jabul Baudan exploration license in The Kingdom of Saudi Arabia's Jabal Said Belt. The property encompasses over 200 square kilometres in an area recognized for its high prospectivity for copper gold and zinc mineralization. The region is known for its massive volcanic sulfide (VMS) deposits, including the world-class Jabal Sayid mine and the promising Umm and Damad deposit.

About SGS Canada Inc.

SGS is the world's leading testing, inspection and certification company, with a network of over 2,500 laboratories and business facilities across 115 countries and a team of over 100,000 professionals. SGS Geological Services, based in Quebec City, Québec, provides ore body modelling and resource estimation, mine engineering, technical reports under NI 43-101, JORC and S-K 1300, and technical audits and due diligence, drawing on more than 45 years of geostatistical expertise and more than 1,600 consulting projects worldwide. SGS's Metallurgical Centre of Excellence in Lakefield, Ontario has served the Canadian and global mining industry since 1941 and has completed more than 22,000 projects; together with SGS's Quebec City laboratory, it carried out the Lion Zone metallurgical test work reported in this news release.

For further information, readers are encouraged to contact:
Power Metallic Mines Inc.
The Canadian Venture Building
82 Richmond St East, Suite 202
Toronto, ON

Neither the TSX Venture Exchange nor its Regulation Services Provider accepts responsibility for the adequacy or accuracy of this release.

Cautionary Note Regarding Forward-Looking Statements

This message contains certain statements that may be deemed "forward-looking statements" concerning the Company within the meaning of applicable securities laws. Forward-looking statements are statements that are not historical facts and are generally, but not always, identified by the words "expects," "plans," "anticipates," "believes," "intends," "estimates," "projects," "potential," "indicates," "opportunity," "possible" and similar expressions, or that events or conditions "will," "would," "may," "could" or "should" occur. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance, are subject to risks and uncertainties, and actual results or realities may differ materially from those in the forward-looking statements. Such material risks and uncertainties include, but are not limited to, among others; the timing for producing a PEA and for various drilling plans, including the benefits of drilling to further depth; the ability for inferred mineral resources to be upgraded to indicated mineral resources; the availability and criteria of various government tax credits and incentives for critical minerals and the risks that such incentives change; the ability to raise sufficient capital to fund expanded exploration and development efforts going forward and to conduct drilling and exploration; to maintain its mineral tenures and concessions in good standing; to explore and develop its projects; changes in economic conditions or financial markets; the inherent hazards associates with mineral exploration and mining operations; future prices of copper, nickel and other metals; changes in general economic conditions; accuracy of mineral resource and reserve estimates; the potential for new discoveries; the ability of the Company to obtain the necessary permits and consents required to explore, drill and develop the projects and if accepted, to obtain such licenses and approvals in a timely fashion relative to the Company's plans and business objectives for the applicable project; the general ability of the Company to monetize its mineral resources; and changes in environmental and other laws or regulations that could have an impact on the Company's operations, compliance with environmental laws and regulations, dependence on key management personnel and general competition in the mining industry.

View original content to download multimedia:https://www.prnewswire.com/news-releases/power-metallic-defines-high-grade-maiden-resource-at-lion-averaging-3-9-cueq-with-85-indicated-and-significant-expansion-potential-302871947.html

SOURCE Power Metallic Mines Inc.