Fortuna Achieves Major Depth Breakthrough at Sunbird: Exceptional 6.1 g/t Au Over 18.9 Meters at 492-Meter Level in Côte d'Ivoire

Fortuna Mining Corp. (NYSE: FSM | TSX: FVI) unveiled compelling exploration results from the Sunbird deposit at the Séguéla Mine in Côte d’Ivoire on February 12, 2026, marking a significant milestone in the company’s resource expansion strategy. The latest drilling campaign has successfully pushed mineralization boundaries deeper while expanding a secondary high-grade zone, demonstrating the deposit’s substantial vertical and lateral potential.

Standout Drilling Performance: The 492-Meter Strike

The most striking result came from drill hole SGDD148, which delivered a 6.1 g/t Au intercept spanning an estimated true width of 18.9 meters from the 492-meter depth level—a distance that exemplifies how mineralization persists in the deeper portions of the deposit. This result alone suggests that the economic footprint of the Sunbird deposit extends significantly beyond previous estimates. The same hole returned even higher-grade intersections, including 73.5 g/t Au over 0.7 meters, underscoring the presence of discrete ultra-high-grade shoots within the broader mineralized envelope.

Paul Weedon, Senior Vice President of Exploration, highlighted the significance of the campaign: “Our results demonstrate that high-grade mineralization remains wide open at depth, offering meaningful upside for resource growth.” With five dedicated drill rigs focused exclusively on Sunbird, Fortuna’s exploration intensity reflects confidence in the deposit’s expansion potential.

Multi-Hole Validation: Consistent High-Grade Returns

Beyond the benchmark 492-meter result, the drill program uncovered multiple high-quality intercepts across nine principal drill holes. Hole SGRD2477 returned two notable zones: 10.9 g/t Au across 2.1 meters from 483 meters (including 23.5 g/t Au over 0.7 meters), plus an additional 13.9 g/t Au across 4.9 meters from 489 meters (encompassing 27.5 g/t Au over 2.1 meters).

Hole SGRD2491 demonstrated the deposit’s consistent quality, yielding 5.2 g/t Au over 8.4 meters from 513 meters, complemented by deeper mineralization of 8.2 g/t Au over 8.4 meters from 528 meters. The deepest intercept in that hole reached 29.6 g/t Au over 1.4 meters at 533 meters, reinforcing the pattern of higher-grade zones increasing with depth.

Linking the Upper and Lower Shoots: Infill Success

Fortuna’s strategy extended beyond pure extension drilling. Infill work targeting the connection between the upper and lower mineralized shoots yielded substantial results, including 4.1 g/t Au across 11.9 meters from 499 meters depth in hole SGRD2487. This suggests that the two shoots may be part of a larger, more continuous mineralized system—a development that could significantly enhance overall resource economics.

The deepest reach came from hole SGDD149, which intersected 13.0 g/t Au over 4.2 meters from 686 meters depth, with an ultra-high-grade intercept of 31.1 g/t Au over 1.4 meters, extending mineralization approximately 400 meters beyond the existing Mineral Resource envelope.

Robust Quality Standards and Independent Verification

All 22 completed drill holes and 9,816 meters of drilling adhered to stringent quality assurance protocols. Samples were processed through ALS Global’s facility in Yamoussoukro and Bureau Veritas’ laboratory in Abidjan, with final gold analysis conducted in Ouagadougou or Abidjan. The analytical protocol employed a standard 50-gram fire assay with atomic absorption finish, while samples exceeding 10 ppm gold underwent gravimetric verification.

Fortuna’s quality control framework included systematic insertion of blanks, duplicates, and standards, supplemented by independent QA/QC measures from both ALS and Bureau Veritas. Paul Weedon, a Qualified Person under National Instrument 43-101 and member of the Australian Institute of Geoscientists, personally verified all data disclosed in the release.

Forward Outlook: 2026 Expansion Program

The results from the post-June 30, 2025 data cutoff drilling provide compelling evidence that Sunbird’s mineralization remains open at depth and along strike. With mineralization now confirmed approximately 400 meters deeper than the existing resource envelope, Fortuna has signaled a continuation of the drilling program throughout 2026. Each successive campaign is expected to refine the resource model and potentially unlock additional reserve tonnage at economic grade thresholds.

Fortuna Mining Corp. operates three active mines across Argentina, Côte d’Ivoire, Mexico, and Peru, with an exploration portfolio including the Diamba Sud Gold Project in Senegal. The company maintains a commitment to sustainable production that balances operational efficiency with environmental stewardship and community engagement.