The Argyle diamond mine is situated in the Kimberley region in the far north of Western Australia, and is the world's largest single producer of diamonds. The Kimberley region is very hot in climate, with an average temperature of over 40°C during the wet season (from October to March). Production in the Argyle mine began in 1985 and it is operated by the Argyle Diamond Mines Joint Venture, fully owned by Rio Tinto since 2002. Since coming into operation, Argyle has produced nearly 650 million carats of diamonds, and its total annual production of diamonds is over 25 million carats.
Colored Australian Diamonds
Colored Australian diamonds are among the most treasured and valued of all earth's gems.
Most of its production is colorless or nearly so, and only a very tiny proportion is fancy colored. Nevertheless, Argyle produce more colored diamonds than any other source.
The brand Argyle, named after the mine, is responsible for selling the mined diamonds and has become synonymous with quality colored diamonds. The mine produces fancy colored diamonds in variety of colors, but it is most known for its fancy pink diamonds.
Fancy Pink Diamonds
Some of the most rare and sought after gems are the Australian fancy pink diamonds. The mine produces between 90% and 95% of the world's pink diamonds, being the world's foremost source of these precious gems. However, an extremely small proportion of Argyle's diamonds production is actually pink, in fact less than one tenth of 1% is classified pink, but it still amounts to couple of thousands of carats a year.
Argyle has sold pink diamonds to private customers for up to $1 million a carat. As pink is one of the rarest colors found in real diamonds, even secondary colors demand a higher price depending on depth and strength of color.
Other Colored Diamonds
The Argyle mine is producing other naturally colored diamonds, though in limited quantities. A limited quantity of fancy yellow diamonds, fancy blue diamonds in a wide range of shades (from sky blue to a more "steely" color than sapphire) are recovered from the Argyle mine, as well as a limited quantity of fancy green diamonds. Champagne diamonds, which are naturally colored diamonds produced in a wide range of colors, from light straw to rich cognac, are available in relatively larger quantities.
The future
Working toward an underground future began back in 2001. Rio Tinto has been evaluating the possibility of establishing an underground mine below the current pit, and spent some AU$70 million on carrying out a feasibility study on underground mining. The funding of the project was approved in December 2005, after a great deal of work. It is planned that Argyle will conclude mining in the open pit by 2008, when the mine is supposed to become a fully underground operation.
