Stillwater Critical Minerals Engages Mine Technical Services to Complete an Updated Mineral Resource Estimate at Stillwater West in Montana, USA

VANCOUVER, BC / ACCESS Newswire / October 27, 2025 / Stillwater Critical Minerals Corp. (TSX.V:PGE)(OTCQB:PGEZF)(FSE:J0G) (the "Company" or "Stillwater") is pleased to announce that it has engaged Mine Technical Services ("MTS") to complete an updated NI 43-101-compliant Mineral Resource Estimate ("MRE") for the Company's 100%-owned Stillwater West critical minerals project (Ni-Cu-Co-PGE-Au) in Montana, USA.

Highlights

• The updated Mineral Resource Estimate ("MRE") is expected in H1 2026 and will mark the next step in advancing Stillwater West as a potential large-scale source of ten minerals listed as critical in the U.S.

• Stillwater West hosts nickel, copper, cobalt, chromium, platinum, palladium, rhodium, ruthenium, iridium, gold, and osmium - a unique mix of battery, alloy, and platinum group metals essential to clean energy, defense, and technology supply chains.

• The update will build on the January 25, 2023, Inferred Mineral Resource estimate as detailed below.

• Results will support further technical studies and economic assessments.

• MTS has completed a site visit and is updating deposit models to incorporate new data, improved geologic domaining, geostatistics, and structural controls - leveraging insights from the Platreef district in South Africa.

• The work is being led by Mr. Timothy Kuhl (MTS) and Dr. Danie Grobler (Stillwater) who together previously worked with the late Dr. Harry Parker on the resource estimation and technical reports for Ivanhoe Mines' Platreef Mine.

• The updated MRE will incorporate 14 drill holes totaling 5,781 meters ("m") from the 2023 and 2025 programs, plus select historic holes not included in the current estimate.

• The 2025 drill campaign is now complete, totaling 3,471m in eight holes, with all assays pending.

President and CEO, Michael Rowley commented, "Reuniting the team responsible for defining the large-scale polymetallic critical mineral resources at Ivanhoe's Platreef Mine to complete an updated resource estimate is an important step towards evaluating production scenarios at Stillwater West. With platinum, palladium, rhodium and gold all demonstrating strong recent market performance, Stillwater West offers significant leverage to these precious metals. Based on the Company's current NI 43-101 Mineral Resource estimate, Stillwater owns one of the largest development-stage PGM (Pt, Pd, Rh, Au) resources in the United States. Our work applying those robust mine models to similar geology in Montana is timely given America's focus on securing domestic supplies of the commodities we have at Stillwater West. We continue to have a very positive reception from all levels of government and look forward to updates on all activities in the near term."