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
Merlin diamond mine Merlin diamond mine The Merlin diamond mine is one of only three diamond mines in Australia. The mine is located in the Northern Territory of Australia, about 80 kilometres south of Borroloola. The mine operated for a period of about four years from 2000 to mid-2003, during which time it produced about 500,000 carats (100 kg) of high quality diamonds. The Merlin mine has an unusually high proportion of gem-quality diamonds: 65% of production is gem-quality, and only 35% is classified as near-gem or industrial quality. This compares to a worldwide average of just 20% gem-quality diamond production at diamond