Tango Mining sold a 19.87-carat rough diamond for $4,358 per carat, one of a number of high-value stones up for tender from its Oena project in South Africa.
The miner sold 230 stones totaling 531.82 carats from its May 9 to July 7 production. It achieved an average price of $1,382 per carat for rough at the sale.
The company also sold a 49.6-carat diamond for $2,561 per carat, a 16.65-carat rough for $2,126 per carat, and a 24.97-carat stone for $1,101 per carat.
In addition, Tango is conducting trial mining in Angola and an exploration project in Liberia.