A 04.73 carat D color Type IIa diamond, left, and a 151.52 carat Type I yellow diamond. Gem Diamonds Ltd. discovered in Lesotho Mine last year. Source:: Gem Diamonds Ltd.
INTERNATIONAL - A small diamond miner that digs for the precious stones in the mountainous kingdom of Lesotho keeps unearthing huge stones.

Gem Diamonds Ltd.’s latest discovery is a 152-carat, top white color Type IIa diamond from its Letseng mine in Lesotho, Southern Africa, the company said Wednesday. It’s the sixth find bigger than 100 carats this year, including a 910-carat stone that’s the fifth biggest in history.

The company’s seen a return to form after years of smaller hauls. It found just seven stones bigger than 100 carats for the whole of 2017 and five the year before. Gem’s share price sank to a record low last year as prices sank and it had to close a new mine in Botswana.

The Letseng mine is famous for the size and quality of the diamonds it produces and has the highest average selling price in the world. Gem sold a 357-carat stone for $19.3 million in 2015 and in 2006 found the 603-carat Lesotho Promise. Its diamonds sell for an average of more than $2,000 a carat, the highest in the industry.