Argyle diamond mine at the Ekati mine, both in Canada. However, Argyle has two to four times the concentration of diamonds (ore grade) of these mines. This makes extraction economically feasible, as mine costs are mostly related to the amount of ore processed, not the amount of diamond extracted. In 2005, Rio Tinto was given the go-ahead to a future expansion project, moving it from an open pit to an underground mine. This plan was postponed; in September 2010 Rio Tinto announced fresh plans to develop an underground mine beneath the existing pit, increasing annual production to 9 million tonnes of ore. The
Ekati Diamond Mine company. The next kimberlites to be developed at Ekati will be mined using open pit methods and are named Jay and Sable, discovered in 1993 and 1995, respectively. Underground mining of the Misery kimberlite will commence in 2020, after open pit operations have been completed. Ekati Diamond mine, which is currently operated by Dominion Diamond is scheduled to remain operational until 2033. On November 13, 2012, CBC reported that the Harry Winston Diamond Corporation (now: Dominion Diamond Mines), 40% owners of Diavik Diamond Mine, would buy Ekati for US$500 million. Diamonds at the Ekati site are found in 45- to