Quantum Identifies Mica as Key Carrier of Critical Elements at NMX East, Québec

Preliminary assays from pegmatite core reveal strong correlation between mica content and enrichment of Ga, Rb, Cs, Li, Nb, Sn, and Ta.

Vancouver, BC – September 3, 2025 – Quantum Critical Metals Corp. (TSX.V: LEAP | OTCQB: ATOXF | FSE: 86A1) (“Quantum” or the “Company”) has received assays back on hand selected mica samples from pegmatite core from the NMX East project, located in the Eeyou Istchee James Bay region of Québec.

A sample of pegmatite core was collected and sent to SGS Lakefield for mineralogy, metallurgical and hydrometallurgical studies to better understand the association of gallium (Ga), rubidium (Rb), and cesium (Cs), and to perform hydrometallurgy to remove the metals from the drill core.

As a precursor to the detailed mineralogical studies currently underway at SGS Lakefield, Quantum geologists hand selected three samples to test if Ga, Rb, Cs were associated with the mineral mica. Samples 1 and 2 were thought to be comprised mostly of mica whereas Sample 3 was thought to contain other minerals such as feldspars and quartz.

The samples were sent to AGAT Laboratories in Calgary for assay and X-ray diffraction analysis. Samples with the highest mica content returned the highest values of multiple elements, suggesting that mica is the main host of mineralization. One mica-rich sample containing 72.7 wt% mica (Sample 2) recorded values of 186 ppm Ga, 959 ppm Li, 320 ppm Nb, 3,220 ppm Rb, 347 ppm Sn, and 71.5 ppm Ta. By contrast, a sample with only 0.7 wt% mica (Sample 3) contained much lower values: 21.3 ppm Ga, 23 ppm Li, 10 ppm Nb, 1,180 ppm Rb, 4 ppm Sn, and 1.4 ppm Ta.

This new analysis highlights a strong link between mica content and enrichment of several critical metals, including gallium (Ga), lithium (Li), niobium (Nb), rubidium (Rb), tin (Sn), and tantalum (Ta). These results reinforce the theory of mica acting as a host for mineralization in the NMX pegmatite systems. Additional detailed mineralogy is currently being done at SGS Lakefield which will lead into the hydrometallurgy studies where the metals are extracted from the minerals.

Why Is This Important?

If the detailed mineralogical studies being conducted at SGS align with the preliminary assay results, it is likely to confirm that the critical elements (Ga, Rb, Cs, Nb, Sn, Ta) are hosted within the mica. This is good news for Quantum because this makes it easier to remove these elements from the rock — once that one mineral is isolated from the rock, the hydrometallurgy (removal of the minerals) becomes easier.

Assay QA/QC

The samples were hand selected from ¼ cut drill core. Because of this methodology, the results do not represent the entire interval of 107 metres sampled for metallurgical testing, nor do they represent the ore body itself. The samples were sent to AGAT Laboratories in Calgary. AGAT is ISO 9001:2015 and Standards Council of Canada accredited for mineral analysis. The samples underwent sodium peroxide fusion with ICP-OES and ICP-MS finish.

Quantum Key Developments to Date

• Significant Critical Metals Discoveries
  A detailed reassessment of drill core assays from both Québec projects has confirmed elevated and consistent intervals of gallium, rubidium, cesium, niobium, and tantalum, supporting the identification of two distinct gallium-rubidium-cesium mineralized systems within the Company’s portfolio.
• Early Metallurgical Focus to Accelerate Recovery Assessment
  Quantum is prioritizing mineralogical and metallurgical studies ahead of a formal resource estimate to evaluate the economic viability of metal recovery, aiming to fast-track development and position the Company at the forefront of critical metal supply efforts in North America.
• Innovative Gallium Recovery from Mica
  Initial findings suggest gallium may be hosted in mica, a non-traditional source. While gallium is typically extracted as a byproduct of bauxite or zinc processing, historical studies show it can be recovered from mica using floatation followed by hydrometallurgy acid leaching techniques.
• Strengthening Domestic Supply Chains
  In light of China’s December 2024 ban on gallium exports, Quantum’s discoveries represent a timely and strategic opportunity to support North American critical mineral independence across semiconductors, telecommunications, defense, and renewable energy.

Qualified Person

George M. Yordanov, P.Geo., a consultant to the Company, is the Qualified Person who has reviewed and approved the scientific and technical disclosure in this news release.

About Quantum Critical Metals Corp.

Quantum Critical Metals Corp. (TSX.V: LEAP) (OTCQB: ATOXF) (FSE: 86A1) is a Canadian mineral exploration company focused on advancing critical metals projects that power next-generation technologies. With a growing portfolio of promising assets—including the NMX East Gallium-Rubidium-Cesium Project in Québec, the Discovery Gallium-Rubidium-Cesium and polymetallic project in Québec, the Victory Antimony Project in British Columbia, and the newly acquired Prophecy Germanium-Gallium-Zinc Project in British Columbia, among others, the Company is strategically positioned to support the West’s transition to a secure and sustainable critical metals supply.

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Marcy Kiesman, CEO
Telephone: 604.428.2900 or 604.339.2243
Email: info@quantumcriticalmetals.com
Website: www.quantumcriticalmetals.com

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