Stillwater Critical Minerals Corp. (TSX-V: PGE) (OTCQX: PGEZF) (FSE: J0G) is pleased to announce that it has filed an independent technical report prepared in accordance with National Instrument 43-101 – Standards of Disclosure for Mineral Projects for the updated Mineral Resource Estimate at its 100%-owned Stillwater West critical minerals project in Montana, USA.

The Technical Report supports the updated Mineral Resource Estimate announced on August 27, 2026, which more than doubled the project’s Inferred Mineral Resource and established its first Indicated Mineral Resource. The updated estimate represents a significant advancement in the Company’s understanding of the Stillwater West mineral system and provides a strengthened technical foundation for continued exploration, metallurgical testing, engineering and future economic evaluation.

Highlights of the 2026 Mineral Resource Estimate include:

• First Indicated Mineral Resource: 29.4 million tonnes grading 0.38% total nickel equivalent at a 0.20% NiTEq cut-off grade.
• Expanded Inferred Mineral Resource: 805.1 Mt grading 0.34% NiTEq at a 0.20% NiTEq cut-off grade.
• Grade Within Scale: At a 0.35% NiTEq cut-off grade, the MRE includes 254.6 Mt grading 0.51% NiTEq in the Inferred category and 12.3 Mt grading 0.47% NiTEq in the Indicated category. At a higher 0.50% NiTEq cut-off grade, the estimate includes 83.0 Mt grading 0.71% NiTEq Inferred and 5.28 Mt grading 0.54% NiTEq Indicated.
• Significant Contained Critical Minerals: Approximately 4.8 billion pounds of nickel, copper and cobalt, and 7.4 million ounces of platinum, palladium, gold and rhodium are estimated in the base case (see Tables 1 and 2 in the August 27, 2026, news release for grades and additional details).
• Strategic U.S. Critical Mineral Resource: The updated estimate positions Stillwater West as the largest known rhodium deposit in North America and the largest nickel-PGE and cobalt deposits in an active U.S. mining district.
• Additional Chromium Resource: An estimated 6.6 billion pounds of chromium in the Inferred category, which is not included in the NiTEq calculation.

Michael Rowley, President and CEO of Stillwater Critical Minerals commented: “The filing of this technical report represents another important milestone in advancing Stillwater West as a potential major primary source of critical minerals within the U.S. The substantial expansion of our Mineral Resource and the establishment of our first Indicated Resource demonstrate the scale and growing geological confidence of this unique polymetallic system and the geological model we have developed. With a strengthened technical foundation and significant potential for continued expansion, we remain focused on advancing the project toward future metallurgical, engineering and economic studies.”

NI 43-101 Technical Report

The Technical Report, entitled “Stillwater West Ni-PGE-Cu-Co-Au Project, Montana, USA, NI 43-101 Technical Report”, is dated October 16, 2026, and was prepared by Mine Technical Services, including independent Qualified Persons Mr. Timothy O. Kuhl, RM SME, and Dr. Ted Eggleston, P.Geo.

The updated Mineral Resource Estimate incorporates additional drilling, historical data verification, refined geological and structural interpretations, and updated resource modelling across the Chrome Mountain and Iron Mountain areas of the Stillwater West project.

The Technical Report is available under the Company’s profile on SEDAR+ at sedarplus.ca and on the Company’s website at criticalminerals.com.

The Mineral Resource Estimate disclosed in the Technical Report is unchanged from the results announced by the Company on August 27, 2026. Readers are encouraged to review the full Technical Report for detailed information regarding the Mineral Resource Estimate, estimation methodology, assumptions, parameters and associated risks.

Upcoming Events

Company representatives will be attending the following events and look forward to discussing the 2026 MRE and upcoming catalysts:

• AEMA Annual Meeting – Sparks, NV, USA, December 6-11, 2026.
• Montana Mining Association Winter Meeting – Billings, MT, USA, December 8-9, 2026.
• VRIC 2027 – Vancouver, BC, Canada, January 24-25, 2027.
• AME Roundup – Vancouver, BC, Canada, January 25-28, 2027.
• 121 Events – Cape Town, South Africa, February 8-9, 2027.
• PDAC 2027 – Toronto, ON, Canada, March 7-10, 2027.
• Swiss Mining Institute – Zurich, Switzerland, March 18-19, 2027.

About Stillwater Critical Minerals Corp.

Stillwater Critical Minerals is a mineral exploration and development company advancing its 100%-owned Stillwater West Ni-PGE-Cu-Co-Cr + Au project in the Stillwater mining district of Montana, USA. Stillwater West is directly adjacent to Sibanye-Stillwater’s operating Stillwater mines and processing infrastructure, the only primary platinum group element-producing complex in the United States. An NI 43-101 Mineral Resource Estimate released in August 2026 positions Stillwater West as one of the largest nickel and platinum group element resources in the United States and includes ten minerals currently listed as critical. With strategic investments by Glencore and an experienced technical team with expertise in Bushveld- and Platreef-style systems, the Company is advancing Stillwater West through ongoing resource expansion, resource upgrades and technical studies.

Stillwater also holds a 49% interest in the high-grade Drayton-Black Lake-gold project adjacent to Nexgold Mining’s development-stage Goliath Gold Complex in northwest Ontario, currently under an earn-in agreement with Heritage Mining, and the Kluane PGE-Ni-Cu-Co critical minerals project on trend with Nickel Creek Platinum’s Wellgreen deposit in Canada’s Yukon Territory. The Company also holds the Duke Island Cu-Ni-PGE property in Alaska and maintains a back-in right on the high-grade past-producing Yankee-Dundee in BC, following its sale in 2013.