Gem Diamonds said trading across its Letšeng mine in Lesotho tracked within full-year 2026 guidance during the six months to 30 June, even as carats recovered fell versus the first half of 2025.
The London-listed miner, which operates the Letšeng kimberlite mine known for exceptional-quality large diamonds, attributed the lower output to a mine plan that drew production mainly from the lower-grade Main Pipe rather than the higher-grade Satellite Pipe.
Eight diamonds each sold for more than $1 million during the period, generating combined revenue of $16.1 million, while the highest price achieved was $32,908 per carat for a 52.24 carat white diamond.
Three diamonds above 100 carats were recovered in the period, including a 346.99 carat white stone found in June and named the "Lesotho Jubilee" to mark the 60th anniversary of Lesotho's independence; it will be sold after the period end.
Chief executive Clifford Elphick said synthetic diamonds continue to weigh heavily on prices for lower-quality, smaller rough stones, prompting some mines with similar production profiles to suspend operations, but that Letšeng's large, exceptional-quality output has proved more resilient, with "encouragingly strong demand leading to an improvement in prices during H1 2026".
Production for the remainder of the year will continue to be sourced from the Main Pipe while the company prepares for the next cutback in the Satellite Pipe.
