The History of Argyle Diamonds
In the first article in this series we introduced you with the Argyle diamonds. This part will cover their history
Many stories are told about the Argyle mine: how it was discovered and the stunning quality of its pink diamonds. The one thing we know for certain is that the Argyle mine is counted among the most prominent and prolific diamond mines in the world. Particularly when it comes to fancy color diamonds.
Argyle mine history
Western Australia’s, East Kimberly region is the home of the Argyle mine. Back in the 1960s prospectors looking for gold, found mineral deposits in the northern area of the region; in Smoke Creek near to Lake Argyle. However, it was not until some time in the 1970’s that suspicions began to arise that there may be a diamond source.
Geological studies based out of the University of Western Australia indicated a similarity between the Lamprodite rock common to the region and Kimberlite; a type of rock frequently associated with diamonds. With funding from Ashton Mining Ltd., an exploration of the area commenced. The result of which was the discovery of small diamonds.
In 1976 CRA Ltd. took over management of the budding mine. Setting two clear objectives, first to locate a diamond larger than 0.25-carat and second to pinpoint a pipe that would yield these diamonds. A great part of the company’s strategy was dependant on the rainy season. The company hoped the wet conditions would lead them to exposed pipes where diamonds were washed away to the waterbeds. It is CRA that later became what we now know as Rio Tinto Ltd.
Making a success of the mine presented some challenges. The Kimberly region is remote. Zero access to infrastructure made the company’s efforts arduous and costly. Helicopters were needed to take sample collectors to various Kimberley waterbeds and it was years before research yielded positive results. In the end all of the hard work paid off and by 1979 geologists were able to pinpoint substantial alluvial diamond deposits. It was decided that Smoke Creek in the Ragged Ranges was a good location for the mine. In the following two months, a diamond-bearing Lamproite pipe called “AK1 pipe” was identified.
Following this, things moved quickly with alluvial mining operations at Smoke Creek and by 1984 construction began on the Argyle mine. Within a year and a half, the company had built a much needed infrastructure and spent $450 million for the AK1 plant construction: making 1984 the year the Argyle mine was officially commissioned.
More than half a billion carat diamonds have been unearthed since then. Today 95 percent of the Argyle mines overall productivity goes to industrial grade diamonds and 5 percent to gem quality.
Total gem diamonds productivity breaks down to:
• 80 percent brown
• 16 percent yellow
• 2 percent grey
• 2 percent white
• 1 percent is pink and green
The percentage in pink diamond production of the Argyle mine may seem low. However, this is quite deceptive as it accounts for 90-95% of pink and red diamond supplies globally. This makes the Argyle mine the most consistent source for these colored diamond gems. Statistics validate Argyle’s triumph as the first commercial Lamproite pipe diamond mine. The record shows earlier efforts to mine a Lamproite pipe in the state of Arkansas, USA failed commercially.