Argyle diamond mine of tunnelling, the Argyle underground block cave development was officially completed. In 2013, Argyle is estimated to produce 10.2 million carats with an average per carat price of $25/carat. The Argyle diamond mine is also notable for being the first successful commercial diamond mine exploiting a volcanic pipe of lamproite, rather than the more usual kimberlite pipe; much earlier attempts to mine diamonds from a lamproite pipe in Arkansas, USA were commercially unsuccessful. The Argyle mine is owned by the Rio Tinto Group, a diversified mining company which also owns the Diavik Diamond Mine in Canada and the Murowa Diamond
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