Fortuna Expands Southern Arc Mineralization with Drill Intercept of 1.7 g/t Au over 29.6 meters and a further 2.0 g/t Au over 20.0 meters from DSDD574 at the Diamba Sud Gold Project, Senegal

VANCOUVER, British Columbia, Dec. 08, 2025 (GLOBE NEWSWIRE) -- Fortuna Mining Corp. (NYSE: FSM | TSX: FVI) is pleased to report additional exploration drilling results from the Southern Arc deposit at its Diamba Sud Gold Project in Senegal. Diamba Sud is a PEA-stage project with robust economics, highlighted by an estimated after-tax NPV5% of US$563 million and an IRR of 72% at a gold price of US$2,750 per ounce. The project is currently advancing toward a feasibility study and a construction decision targeted for the second quarter of 2026.