Fortuna logs high-grade gold in Senegal, extends deposit’s depth

New drilling by Fortuna Mining (NYSE: FSM; TSX: FVI) at its Diamba Sud project in Senegal could expand the property’s mineral reserve.

Hole DSR1149 in the Southern Arc zone cut 40.8 metres of 3.9 grams gold per tonne from 228 metres downhole, extending the deposit at depth, Fortuna said Tuesday in a statement. Hole DSDD699 in the same zone cut 12 metres grading 6.8 grams gold per tonne from 96 metres depth.

Diamba Sud is among the key development assets that Fortuna is counting on to lift annual output to 500,000 gold-equivalent oz. by 2028 from a maximum forecast of 305,000 oz. this year. The Vancouver-based company also operates mines in Peru, Argentina and Côte d’Ivoire.

Drilling results at Diamba Sud “support near-pit growth,” National Bank Financial mining analyst Mohamed Sidibé said Tuesday in a note. “Parallel structures to the southeast also remain open as they remain untested.”

Fortuna plans to incorporate the Southern Arc results into mineral resource and reserve reporting as at year-end. Further step-out drilling is planned for 2027.

Largest target

Exploration drilling at the nearby Bambadji properties has begun at Kabewest, the area’s largest and most advanced drill-defined target, Fortuna also said Tuesday. Assays are pending.  

Six drill rigs are operating as part of an $8 million (C$11 million) drilling campaign for the rest of 2026. Kabewest sits 2.3 km from the proposed Diamba Sud plant site. 

Geological examination of initial drill core samples has highlighted strong similarities to the breccia-hosted mineralization at Diamba Sud, senior vice president of exploration Paul Weedon said in the statement.

Strike extensions

Other Southern Arc results reported Tuesday include hole DSR1132, which cut 20 metres grading 4.5 grams gold from 65 metres. Hole DSR1128 cut 12.8 metres of 7.8 grams gold from 103 metres downhole.

Since releasing its previous exploration update in February, Fortuna has drilled 196 reverse circulation and diamond drilling holes at Southern Arc, covering 36,592 metres. The program successfully identified depth and strike extensions to the northeast and southwest.

Mineralization at Southern Arc occurs in networks of small veins and areas where pyrite and silica fill the surrounding rock. It is often found near breccias and carbonate-rich rocks. The area also shows widespread alteration by hematite, a feature seen at other deposits on the Diamba Sud property.

Diamba Sud holds probable reserves of 20.5 million tonnes grading 1.75 grams gold for contained metal of 1.15 million oz. gold, according to an estimate dated April 2026.

2028 start

Gold production at Diamba Sud should start in the second quarter of 2028, Fortuna says. The company is targeting a final investment decision this quarter and says negotiations over a tax stability agreement with Senegal are in their final stages, according to an Oct. 7 update.  

Using a 5% discount rate and a gold price of $3,500 per oz., Diamba Sud has a net present value of $1 billion after tax, a 60% internal rate of return and a one-year payback period, according to a feasibility study released in June.

The project represents 18% of Fortuna’s C$23.47-per-share net asset value, Sidibé says.

Fortuna shares fell 3.4% to C$15.04 Tuesday morning in Toronto, valuing the company at about C$4.5 billion ($3.2 billion). The stock has traded between C$10.78 and C$18.99 in the past year.