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
Argyle diamond mine over a period of 18 months at a cost of A$450 million. The mine was commissioned in December 1985. "Several of this article's references contain excellent maps and photographs of the mine and examples of diamonds produced there, which cannot be placed in this article due to copyright limitations. The reader is especially directed to Shigley, Chapman, and Ellison's article, "Discovery and Mining of the Argyle Diamond Deposit, Australia" (Gems & Gemology, Spring 2001)." Argyle diamond mine The Argyle Diamond Mine is a diamond mine located in the East Kimberley region in the remote north of Western Australia. Argyle is