For hundreds of years India was the world’s source of diamonds. However, as that supply started to dwindle, there were smaller finds in Borneo and Brazil. The discovery of a large diamond deposit in South Africa in the mid-1800s helped to meet the world’s increasing appetite for these gems. Today, diamonds are also mined in South Africa, Botswana, the Democratic Republic of Congo, Australia, Canada, Zimbabwe, Namibia, Angola, throughout many countries in western Africa and Russia.
Diamonds in Australia were recorded in the Bathurst area, New South Wales in 1851. Significant quantities also were mined from alluvial deposits at Copeton and Bingara, near Inverell in north-eastern New South Wales, from 1867 to 1922 and minor production resumed at Copeton in 1997, but has since stopped. Numerous minor occurrences of diamond have been recorded elsewhere in Australia.
Creek sediment sampling and other exploration techniques in the early to mid-1970s led to the discovery of 23 diamondiferous but low-grade pipes at Ellendale in 1976 and the Argyle deposit in 1979. Shark cages were used in the late 1980s to protect scuba divers against crocodiles while they sampled diamonds (eroded from land) from the seabed off river mouths in the north-east Kimberley region. Small numbers of gem-quality diamonds have since been recovered using an airlift drill attached to a boat.
It was not until the late 1970’s that geologists found the Argyle pipe in the remote Kimberley area of Western Australia: the richest diamond deposit in the world. Argyle is the world’s largest volume producer of diamonds, supplying a third of the world’s diamonds every year and since the late 1980s, over 90% of the world’s pink diamond supply has come from Rio Tinto’s Argyle mine. The Argyle deposit contains a large proportion of the world’s economic diamond resources and has some of the highest diamond grades in the world. Argyle sells 100% of its product direct to the world market. The majority of Argyle’s diamonds are sold as “rough” or uncut diamonds. These are sorted and prepared for in relatively small resources of alluvial diamonds were worked nearby in Smoke Creek (Argyle Alluvials) and the Bow River Mine. A number of small diamond ‘pipes’ with a much higher proportion of gem-quality diamond than Argyle have been mined at Merlin in the Northern Territory and Ellendale in the west Kimberley region, both of which are currently not in operation..
