PMET signs MoU with Mitsui and MWCC to advance on-site lithium refining in Quebec

MONTREAL, June 18, 2026 /PRNewswire/ -- June 18, 2026 – Sydney, Australia

Highlights

• PMET has entered into a non-binding Memorandum of Understanding ("MOU") with Mitsui & Co., Ltd. ("Mitsui") and Microwave Chemical Co., Ltd. ("MWCC") to jointly evaluate the application of MWCC's proprietary microwave calcination technology to produce higher-value lithium products on-site at Shaakichiuwaanaan.
• The collaboration builds on PMET's recently announced Concept Study (refer to News Release, 14 June 2026), which identified a potential pathway to produce battery-grade lithium carbonate at site and capture additional value within the lithium supply chain.
• Microwave calcination has the potential to support electric calcination at site, which is the first step in the production of value-added lithium chemicals from spodumene concentrate, leveraging Québec's low-cost, renewable hydroelectric power as a potential alternative to conventional fossil fuel-based calcination.
• Pilot plant testing in Osaka will use spodumene samples supplied from Shaakichiuwaanaan, with MWCC leading the technical testing program and Mitsui supporting the evaluation of future commercialization and project development pathways.
• The initiative is aligned with PMET's longer term diversification strategy to reduce logistics intensity and enhance supply chain resilience, with potential benefits including reduced transportation requirements and lower truck traffic, reduced reliance on offshore conversion capacity, and the creation of a higher-value lithium product in Québec.
• The MOU is non-binding and non-exclusive, and any future commercial deployment remains subject to successful testing and demonstration at scale, technical and economic evaluation, definitive agreements, funding, permitting, approvals and other customary conditions.

Ken Brinsden, CEO and Managing Director, comments: "This collaboration is a direct extension of the downstream growth strategy we outlined recently for Shaakichiuwaanaan. Our Concept Study identified a potential pathway to produce battery-grade lithium carbonate on site, and microwave calcination now represents an opportunity to evaluate one of the key enabling technologies that could support that vision.

"Shaakichiuwaanaan is already one of the world's premier hard-rock lithium projects, and the collaboration with Mitsui and Microwave Chemical represents another important step in our strategy to evaluate additional value-creation opportunities beyond spodumene concentrate.

"This MOU brings together PMET's high-quality lithium resource, MWCC's proprietary microwave calcination technology, and Mitsui's global project development and commercialization capabilities. It is an important next step in assessing how Shaakichiuwaanaan can leverage Québec's low-cost renewable hydroelectricity into a more integrated, Western-facing lithium supply chain that supports Québec, Canada and allied markets," added Mr. Brinsden.

PMET Resources Inc. (the "Company" or "PMET") (TSX: PMET) (ASX: PMT) (OTCQX: PMETF) (FSE: R9GA) is pleased to announce that it has entered into a non-binding Memorandum of Understanding with Mitsui & Co., Ltd. and Microwave Chemical Co., Ltd. to jointly evaluate the application of proprietary microwave calcination technology to spodumene samples from the Company's 100%-owned Shaakichiuwaanaan Project, located in the Eeyou Istchee James Bay region of Québec, Canada.

Background

Calcination is a key initial processing step in the conversion of spodumene concentrate into downstream lithium chemicals, using heat to convert alpha-spodumene into beta-spodumene for subsequent lithium extraction. Historically, fossil fuels have been the key energy source (in the form of gas and/or coal) to create significant heat and the overall energy required to undertake the phase change (from alpha to beta spodumene).

Mitsui & Co., Ltd. ("Mitsui") and Microwave Chemical Co., Ltd. ("MWCC") have launched a demonstration experiment for the joint development of microwave-based low-carbon lithium ore refining technology. Mitsui provides more information regarding their microwave calcination collaboration with MWCC, on their website.

Québec's large-scale and renewable hydroelectricity scheme generates some of the lowest cost power available in North America. Harnessing this power for application in the spodumene calcination step (i.e. replacing fossil fuels) could represent a key source of competitive advantage for downstream initiatives and therefore motivates PMET Resources to continue its assessment of further value-added and downstream product initiatives at Shaakichiuwaanaan.

Advancing PMET's Downstream Development Pathway

On 14 June 2026, PMET announced the results of a Concept Study evaluating opportunities to convert spodumene concentrate produced at Shaakichiuwaanaan into higher-value lithium chemical products at site. The study identified Primero's ALi® atmospheric leach process as the preferred pathway for further evaluation and successfully produced 99.8% battery-grade lithium carbonate from Shaakichiuwaanaan spodumene concentrate at bench scale.

A key conclusion of that work was that the combination of electric calcination and downstream lithium conversion could potentially leverage Québec's low-cost renewable hydroelectricity to create a more efficient and lower-carbon lithium supply chain while reducing logistics intensity and increasing value capture within Québec and Canada.

The Mitsui-MWCC collaboration is intended to evaluate microwave-assisted electric calcination as a potential enabling technology within this broader downstream development strategy.

PMET – MWCC – Mitsui & Co. MoU

The MOU establishes a collaborative framework for the parties to advance technical evaluation, and potential future commercialization pathways for microwave calcination technology in the lithium industry. Under the terms of the MOU:

• PMET will supply spodumene raw material samples from Shaakichiuwaanaan for pilot plant testing, with 1.5 tonnes of 6.2% Li₂O course spodumene concentrate already shipped to the Osaka pilot facility from its prior pilot DMS testwork programs.
• MWCC will lead the execution of pilot plant testing using its proprietary microwave calcination technology, and
• Mitsui will contribute to the evaluation of the pilot plant results from a project development perspective and where supported will facilitate discussions for potential future commercialization pathways.

The collaboration is intended to assess whether microwave calcination could support PMET's broader value-added downstream products strategy, including the potential production of a lithium-enriched product at site. PMET believes Shaakichiuwaanaan is uniquely positioned to evaluate this opportunity given its scale, location in Québec, potential access to renewable hydroelectric power, and the potential to support a more integrated Western lithium chemicals supply chain.

If successfully developed, electric calcination at or near the mine site could support the use of Québec's low-cost renewable power, reduce reliance on offshore conversion capacity, lower logistics intensity, and significantly reduce the amount of material transported from site by upgrading spodumene concentrate into a higher-value lower volume lithium product.

The Company's concept study to date has identified meaningful potential benefits from on-site conversion, including reduced transport volumes, reduced logistics costs, reduced truck movements, and the potential to support a lower-carbon lithium chemical supply chain.

The collaboration with Mitsui and MWCC is expected to focus specifically on the calcination stage as a potential enabling step in this broader downstream pathway.

Following completion of pilot plant testing by MWCC, the parties expect to review the results and discuss whether to proceed with further evaluation and commercialization-oriented discussions relating to the potential application of microwave calcination technology to PMET's Shaakichiuwaanaan project. The parties may also coordinate efforts to evaluate potential government funding opportunities where aligned with critical minerals strategies and clean energy objectives.

The MOU is non-binding and non-exclusive, except for customary provisions including confidentiality and related matters. Any future commercial arrangement, project development structure, technology deployment, financing or construction decision remains subject to successful testwork, further technical and economic evaluation, definitive agreements, required approvals, and customary development conditions.