• Revenues at Lesotho’s Letšeng diamond mine fell 36% year on year to $97.7 million in 2025.

• A 14% drop in production and a 20% decline in the average price per carat drove the revenue decrease.

• Gem Diamonds sold fewer large stones, with only two diamonds above 100 carats in 2025 versus four in 2024.

In Lesotho, revenues from the Letšeng diamond mine fell 36% year on year in 2025 to $97.7 million, according to a statement released on Wednesday, February 4, by Gem Diamonds. The company owns the mine, which holds the highest average value per carat globally.

The revenue decline reflected both a 14% reduction in production and a 20% drop in the average price per carat achieved. Gem Diamonds recorded an average price of $1,105 per carat in 2025 compared with $1,390 per carat in 2024. While the company did not explain the reasons for the price decline, it sold only two diamonds weighing more than 100 carats during the year compared with four such stones in 2024. The company also sold six diamonds priced above $1 million in 2025 for a combined $9.2 million, compared with six stones sold for a total of $11.6 million in 2024.

The revenue contraction occurred against a challenging global environment for natural diamond producers, who face rising competition from synthetic diamonds that continue to pressure demand and prices. Gem Diamonds said it met its production and revenue targets for 2025 but has not yet released guidance for 2026.

This article was initially published in French by Emiliano Tossou

Adapted in English by Ange J.A de BERRY QUENUM