Lucara details $779m plan to mine beneath Botswana's Karowe diamond pit

Lucara Diamond Corp filed an updated technical report for its Karowe underground project in north-central Botswana, confirming pre-production capital requirements of $779 million through to a planned production start in the first half of 2028. The company has already spent $436 million over five and a half years of development, leaving $343.2 million still to be invested. Lucara president and chief executive William Lamb said "Karowe is a world-class mine," adding that the company looks forward to "continuing to recover large, exceptional diamonds from the underground project."

Sinking two shafts

The project centres on two concrete-lined shafts: an 8.5-metre-diameter production shaft sunk to 767 metres, equipped with two cages and two 21-tonne skips, and a 6.0-metre-diameter ventilation shaft sunk to 729 metres. Both shafts were completed during 2025, a milestone Lucara says materially de-risked the project. The underground mine is expected to process about 37.3 million tonnes of ore over roughly ten years, recovering 4.5 million carats and extending Karowe's revenue-generating life to 2038, with an after-tax net present value of $432.1 million and projected net income exceeding $1.3 billion.

Why it matters

Karowe is renowned for producing some of the largest gem-quality diamonds ever recovered, and an underground extension protects that unusual production profile well beyond the point at which the open pit, expected to close in the first half of 2026, would otherwise have ended the mine's life. For Botswana, whose economy remains heavily dependent on diamond royalties even as the government pushes to diversify, a major life-extension project at an established mine offers steadier near-term revenue than exploration-stage discoveries elsewhere in the country.

What happens next

Recruitment for the underground workforce is under way, with lateral development due to begin in July 2026 and processing continuing in the interim using open-pit ore and stockpiled material. Underground mining is scheduled to begin in the first quarter of 2028, the point at which the project's substantial remaining capital commitment will need to have translated into operating infrastructure.

Sources

• Yahoo Finance / Lucara Diamond Corp: Lucara Announces Updated Feasibility Study for Karowe Underground Project, 06 Jan 2026
• SahmCapital: Lucara Diamond Unveils Updated Feasibility Study for Karowe Underground Mine, 06 Jan 2026

Photo: An open-pit diamond mine in Botswana. Cretep, Wikimedia Commons, Public domain.