Letseng diamond mine
Lesotho · built 1977
The Letšeng Diamond Mine, found in the landlocked Southern African kingdom of Lesotho, is owned by Gem Diamonds, Ltd. and the government of Lesotho, at an elevation of 3,100 m (10, 200 ft) it is the world's highest diamond mine.
Mine data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).