History of Argyle Pink Diamond Mine

The Australian Argyle mine is counted among the most prominent and prolific diamond mines in the world,
especially when it comes to natural Pink Diamonds.

Calleija - Argyle Pink Diamond Mine at night
Calleija - Argyle Pink Diamond Mine from above

The History of Rio Tinto’s Argyle Pink Diamond Mine

Australia’s remote Kimberley region plays host to Rio Tinto’s Argyle Pink Diamond Mine, the source of some ninety percent of the world’s already scare supply of pink diamonds. This isolated and spectacular landscape has always posed challenges for those wanting to explore the area and sample its unique natural delights. The challenges faced by tourists are plenty, however, those faced by geologists and other scientists are greater still.

The rugged wilderness of Western Australia’s Kimberley region has long held a special place in the hearts, and indeed the history, of its Indigenous inhabitants. Rocky gorges, rugged terrain and indescribably beautiful waterways characterise this region, responsible for so much mystery and ancient significance, and for inspiring flocks of holidaymakers, filmmakers and photographers for decades. Also inspired by the regions’ unique natural beauty were the geologists who would go on to discover its hidden secret: The Argyle Pink Diamond.

Australia has not traditionally been regarded as a lucrative source of diamonds of any kind, let alone the rare and spectacular pink diamonds. Geologists spent several years studying the vast, remote, and challenging Kimberley region with the sole purpose of finding what few believed existed. Their tireless efforts were rewarded, and nowadays the area plays host to the most substantial pink diamond mine in the world.

The Kimberley region is, like all the greatest Australian landscapes, host to some of Mother Nature’s most spectacular and devastating weather events. Intense dry seasons and extreme wet seasons make for some of the most punishing and yet breathtaking scenery in the world. It is these infamous wet seasons, responsible for washing away vast land and mineral deposits, which would result in the depositing of one of the world’s most mysterious and sought-after diamonds. Geologists imagined that this regular washing away of mineral deposits could mean that precious stones, if present, would be swept up each rainy season and deposited into what were, by this time, dry creek and river beds.

The University of Western Australia conducted studies in the 1970s which indicated an important similarity between the Kimberley region’s lamprodite rock and kimberlite, a unique type of rock often linked to the presence of diamonds. This discovery was enough to secure funding from Ashton Mining Ltd. and some forty years ago, exploration into the Kimberley region for pink diamonds began.

Initially, the mine’s management had two clear, yet difficult, objectives. First, it was important to find a diamond weighing no less than 0.25 carats, which would indicate that their exploration was not for naught. Secondly, they would search for a layer or ‘pipe’ created by the rainy season’s regular patterns, which would bear these diamonds and allow for commercial mining of the site. Of course, the landscape presented a unique set of challenges, and made it difficult for samples to be exhumed, transported and studied. This gruelling and costly process was tirelessly undertaken by CRA Ltd., who would go on to become Rio Tinto. One fateful day, a geologist working on site came across a diamond embedded, of all places, in an ant hill. This discovery led to the remarkable unveiling of a cache of pink diamonds in a dry creek bed on the site, and the rest, as they say, is history. In 1979, after years of research and exploration, scientists were able to finally locate the holy grail of alluvial diamond deposits in Smoke Creek, of the Ragged Ranges.

What was then known as CRA Ltd. would later become the mining giant we know today as Rio Tinto, and this site in remote Australia would soon attract the rapt attention of master jewellers and jewellery collectors alike, as pink diamonds grew in popularity. By 1984, construction had begun on what we now know was the Argyle mine.

The Argyle mine will exhaust its reserves of diamonds in November 2020, which means that the already extremely rare Argyle Pink Diamonds will become rarer still within just a few short years. With this in mind, an investment today in a pink diamond will not only mean a wise investment in an increasingly valuable gemstone, but an heirloom that will be treasured for generations to come.