(MENAFN- Newsfile Corp) Vancouver, British Columbia--(Newsfile Corp. - October 21, 2025) - Stuhini Exploration Ltd. (TSXV: STU) (OTCQB: STXPF) (WKN: A2PLBV) (" Stuhini " or the " Company ") is pleased to announce that it has engaged Tetra Tech Canada Inc. (" Tetra Tech ") to complete a conceptual-level economic viability assessment of the molybdenum deposit at the Company's 100%-owned Ruby Creek Project, located near Atlin, British Columbia. The engagement marks the first step to advance the economic assessment of Ruby Creek and, contingent on market conditions, to prepare a preliminary economic assessment (" PEA ").

"With molybdenum increasingly recognized as a critical metal in both industrial and green-energy applications, we believe Ruby Creek stands out as one of the more compelling undeveloped molybdenum assets in North America," said Meredith Eades, President and CEO of Stuhini. "Engaging Tetra Tech is an important milestone in understanding the deposit's viability and advancing this part of our portfolio. It also reflects our broader strategy to unlock value on both the development and discovery fronts at Ruby Creek."

A PEA is a scoping-level technical study that provides an early-stage evaluation of a mineral project's potential economic viability. It often incorporates inferred mineral resources to estimate capital and operating costs, revenue forecasts, and development scenarios, helping companies assess whether to advance the project to more detailed studies.

Tetra Tech's assessment will draw on a robust historical archive, including a 2006 feasibility study¹, approximately 74,000 metres of drilling, extensive metallurgical and environmental work, and an existing BC Mines Act permit (currently in care and maintenance). Combined with updated market pricing and cost inputs, the study will provide a refreshed look at the development potential of what the Company believes is one of Canada's most compelling undeveloped molybdenum assets.

Ruby Creek Molybdenum Deposit Highlights:

The Ruby Creek molybdenum deposit is a porphyry-style system with a 2022 NI 43-101 mineral resource estimate²of:

• 433 million pounds of molybdenum in the measured and indicated category (369.4 million tonnes at 0.053% Mo), and
• 43.7 million pounds in the inferred category (41.9 million tonnes at 0.047% Mo).
  (See press release dated March 15, 2022.)

Located in the prolific Atlin Mining District of northwestern British Columbia, the Ruby Creek deposit sits within a stable, mining-friendly jurisdiction, is fully road-accessible, and benefits from proximity to a growing hydro-electric infrastructure initiative led by the Taku River Tlingit First Nation. The project has seen more than 30 years of exploration and development, including:

• ~74,000 metres of drilling.
• A historic 2008 feasibility study.
• A 2022 updated mineral resource estimate (see the Ruby Creek Technical Report filed on the Company's profile on SEDAR+).
• Mineralization remains open in three directions and at depth including 45 metres grading 0.23% Mo at the bottom of hole AD-417.

The deposit is part of the larger 29,734-hectare Ruby Creek Project, which is 100%-owned by Stuhini and hosts 48 documented mineral occurrences, including other zones prospective for gold, silver, and tungsten.

About Tetra Tech:

Tetra Tech is a leading global consulting and engineering firm with extensive experience in resource development, permitting, and economic assessment. Their team has deep expertise in porphyry-style molybdenum systems, having completed the 2022 feasibility study for the Malmbjerg Molybdenum Project in Greenland, a large-scale deposit comparable in mineralogy and scale to Ruby Creek. Tetra Tech previously advanced Ruby Creek to the feasibility study stage in 2008, providing them with a unique familiarity with the project's data and development history.

About Molybdenum:

Molybdenum is a high-strength, high-melting-point metal with critical applications across industrial, energy, and defense sectors. Its primary use is as an alloying element in steel-enhancing strength, corrosion resistance, and hardness. These properties make it essential for demanding environments such as oil and gas pipelines, high-speed rail systems, and structural steel. By improving strength-to-weight ratios, molybdenum enables lighter, more durable steel, reducing material requirements without compromising performance.

Beyond steel, molybdenum is used in catalysts, lubricants, and advanced materials for hydrogen production, water purification, and other emerging clean technologies. Its thermal and structural properties also make it valuable in defense and aerospace alloys.

Molybdenum is recognized as a critical mineral in Canada and increasingly monitored in global supply chain risk assessments due to its strategic importance in industrial resilience and the energy transition.

Qualified Person

Mr. Nicholas Clive Aspinall, M.Sc., P.Eng., is a consulting geologist to Stuhini Exploration and is a "qualified person" as defined by National Instrument 43-101. Mr. Aspinall has verified the data disclosed in this press release, including the sampling, analytical and test data underlying the technical information, and has approved the technical information contained herein.

About Stuhini Exploration Ltd.

Stuhini is a mineral exploration company focused on exploration and development of precious and base metals properties in western Canada. The Company's portfolio of exploration properties includes the flagship Ruby Creek Property, 16 km east of Atlin, BC; and the Big Ledge Property, 57 km south of Revelstoke, BC.

MENAFN21102025004218003983ID1110225841