Gem Diamonds beats market slump with 8 stones worth $16M

Gem Diamonds (LON: GEMD) lifted rough diamond prices in the first half of 2026 as exceptional large stones from its flagship Letšeng mine offset lower production from a planned shift to lower-grade ore.

Average rough diamond prices rose to $1,395 per carat as eight diamonds sold for more than $1 million each, generating combined revenue of $16.1 million. The highest price achieved was $32,908 per carat for a 52.24-carat white diamond. 

The Africa-focused miner recovered three diamonds weighing more than 100 carats during the period, including a 346.99-carat white diamond named the Lesotho Jubilee to mark the 60th anniversary of Lesotho’s independence on Oct. 4. The stone will be sold in the second half of the year, the company said. 

Ore processed increased slightly, while carats recovered declined as mining focused on the lower-grade Main Pipe rather than the higher-grade Satellite Pipe, in line with the mine plan. 

The company said all operational and financial metrics remain within its 2026 guidance.

“Letšeng, with its exceptional quality and large diamond recoveries, has been less impacted, with encouragingly strong demand leading to an improvement in prices during H1 2026,” CEO Clifford Elphick said. 

Market resilience

The results highlight the resilience of Letšeng’s niche production as the broader rough diamond market struggles with competition from synthetic stones. 

While many mines producing smaller, lower-quality diamonds have suspended operations because of weak prices, Letšeng continues to benefit from demand for rare, high-value diamonds. 

Production for the remainder of the year will come exclusively from the Main Pipe while the company prepares the next cutback in the Satellite Pipe, with investors watching whether premium prices continue to offset lower grades.