Fortuna drills 22.7 g/t gold over 21.6 meters at Southern Arc, Diamba Sud Gold Project, Senegal

Executive Summary

• Fortuna Mining reports additional high‑grade drill intercepts from the Southern Arc deposit at Diamba Sud, including a standout hole DSDD488 with 22.7 g/t Au over 21.6 m (true width) and a secondary 258.8 g/t Au interval.
• The new data were obtained after the July 7 resource cut‑off date and will be incorporated into an updated mineral resource estimate slated for Q1 2026, indicating potential significant resource growth.
• Drilling is paused for the rainy season and is scheduled to resume in September 2025, with further results expected by year‑end.

Key Details

• Highlight Intercept – Hole DSDD488: 22.7 g/t Au over an estimated true width of 21.6 m from a downhole depth of 53 m; includes a very high‑grade sub‑interval of 258.8 g/t Au (1.6 m).
• Other Notable Intercepts:
• DSDD418 – multiple intervals up to 23.3 g/t Au over 18.2 m true width.
• DSDD440 – several zones ranging from 6.3 g/t to 19.4 g/t Au, cumulative true width ~16.8 m.
• DSDD444 – 33.5 g/t Au over 1.6 m; total true width 32.0 m.
• DSDD4621 – 21.9 g/t Au over 2.2 m; overall true width 20.8 m.
• DSDD4871 – 33.6 g/t Au over 1.6 m; total true width 22.4 m.
• Overall Program: Since the May 27, 2025 update, a total of 152 RC and diamond drill holes (21,234 m) have been completed at Southern Arc.
• Post‑cut‑off Drilling: 53 holes were drilled after the July 7 data cut‑off; these will feed into the Q1 2026 resource revision.
• Deposit Geometry: Mineralization occurs as fine stockwork vein arrays with strong hematite alteration, open to the south, east, and at depth (current drilling to ~150 m).
• Future Plans: Drilling pause for rainy season; resume mid‑September 2025; additional results anticipated by year‑end.

Notable Quotes

“Exploration drilling at the Southern Arc deposit has continued beyond the data cut‑off date for its maiden resource estimate, returning several high‑grade intercepts.” – Paul Weedon, Senior Vice President of Exploration
“These results further demonstrate the potential for resource growth at Diamba Sud. The deposit remains open to the south, east, and at depth…” – Paul Weedon