The Letseng diamond mine, the world’s highest diamond mine at 3,100 meters above sea level, is located in the Southern African kingdom of Lesotho. The mine is owned by Gem Diamonds Ltd. and the government of Lesotho.
Letseng is famous for producing huge diamonds. It has the highest percentage of large diamonds, which gives it the highest dollar value-per-carat of any diamond mine. In October 2006, miners unearthed the Lesotho Promise – a 603-carat white diamond, the largest to be found in the 21st century to date.
The Lesotho Brown, unearthed in 1967, weighs 601 carats. In 2007, a 493-carat diamond was found, dubbed the Letseng Legacy, and sold for $10 million. In September 2008, Gem Diamonds announced that it has found a 478-carat diamond of high quality, making it the 20th largest diamond ever found. in 2014, Gem Diamonds discovered a 198-carat, white, type IIa rough diamond at the mine.