A blast at Fortuna Mining’s Lindero gold mine in Argentina’s high-Andes. Credit: Henry Lazenby
Fortuna Mining (TSX: FVI; NYSE: FSM) has drilled gold beneath the planned bottom of its Lindero open pit in Argentina’s high-Andes, strengthening its case for adding reserves at the operating mine.
Hole LDH-272 returned 350 metres grading 0.96 gram gold per tonne from surface, including 98 metres averaging 0.91 gram below the pit design, the company reported Tuesday. Lindero lies about 260 km from Salta, the provincial capital, in Argentina’s high-altitude Puna region.
“Broad intersections strengthen the case for including below-pit material in a revised pit and reserve estimate,” National Bank analyst Mohamed Sidibé wrote in a Tuesday note.
Lindero accounts for 32% of National Bank’s forecast company-wide production this year and 28% of its estimated net asset value. The bank’s operating model includes only existing reserves, although its valuation already assigns some value to resources outside the mine plan, Sidibé said.
Fortuna aims to determine how much deeper material can enter an expanded pit and revised mining schedule, with updated resource and reserve estimates planned for release in the first quarter of next year.
Fortuna shares fell about 1.4% to $14.35 by mid-Wednesday in Toronto, valuing the company at $4.27 billion. They’ve traded between $10.78 and $18.99 over the past year.
Deeper targets
The company expanded this year’s diamond drilling program to 8,534 metres in 31 holes from an initial 6,000 metres after encouraging early results. Work focused on improving confidence in inferred resources beneath the southern portion of the planned pit, where earlier drilling had identified higher-grade gold.
A second hole, LDH-259, cut 236 metres averaging 0.85 gram from surface, including 94 metres grading 0.66 gram below the pit design. Both below-pit intervals exceed the 0.54-gram average grade of Lindero’s existing reserves, although drilling alone doesn’t establish that the material can be mined economically.
The reported intervals are downhole lengths. Fortuna hasn’t defined true widths because mineralization forms a roughly circular body associated with a porphyry intrusion.
Crews collected samples to check expected gold recoveries from material scheduled for mining over the next two years. Fortuna aims to finish updating its geological model and pit design by year-end, incorporating the new drilling and indicated resources already identified beneath the pit.
Operating base
Lindero held 64.4 million tonnes of proven and probable reserves grading 0.54 gram gold, containing about 1.1 million oz., at Dec. 31, 2025. Fortuna documentation puts the remaining reserve life at nine years as of that date.
The heap-leach operation, which The Northern Miner visited for an April 2025 report, poured its first gold in October 2020.
Production rose 25% from the second quarter to 26,024 oz. in the three months through September as improved equipment availability lifted crushing and stacking rates, Fortuna said. Lindero’s nine-month output reached 68,398 oz., with Fortuna maintaining the mine’s annual guidance of 92,000 to 102,000 ounces.
Fortuna also operates the Séguéla gold mine in Côte d’Ivoire and the Caylloma silver-lead-zinc mine in Peru. It expects to produce between 281,000 and 305,000 gold-equivalent oz. this year.