Rio Tinto puts last diamonds mined at iconic Argyle up for sale

The Tender comprises five ‘hero’ diamonds named to ensure there is a permanent record of their contribution to the history of the world’s most important diamonds. (Image courtesy of Rio Tinto.)

Rio Tinto (ASX, LON, NYSE: RIO) has unveiled a preview of its final showcase of rare pink, red and blue diamonds from its iconic Argyle mine in the remote east Kimberley region of Western Australia.

Argyle, the world’s biggest and the main global source of high-quality pink diamonds, ceased operations last November, after 37 years in production.

During that time, it churned out 865 million carats of rough diamonds and became the source of about 90% of the world’s prized rose-to-magenta hued stones.

The last Argyle Pink Diamonds Tender, an annual invitation-only event for the past 38 years, will showcase the last collection of gems dug out at the mine. It comprises 70 diamonds weighing 81.63 carats, with a record number of diamonds larger than one carat.

Rio Tinto puts last diamonds mined at iconic Argyle up for sale
Argyle Eclipse, 3.47 carat, radiant shaped Fancy Intense Pink diamond. (Image courtesy of Rio Tinto.)

The collection, called “The Journey Beyond”, makes reference from the 1.5 billion year journey from the formation of the deposit to its discovery and its impact on the world’s diamond and jewellery history, Rio said.

It is headlined with Lot Number 1, Argyle Eclipse, a 3.47 carat diamond that is the largest Fancy Intense Pink diamond ever offered at the event. 

The diamonds will be showcased in Perth, Antwerp, Singapore and Sydney, subject to covid-19 protocols. Bids close on September 1, 2021. 

Diamond pioneer

The closure of Argyle removed about 75% of Rio’s diamond output, yet the impact on the miner’s earnings is expected to be negligible. Diamonds bring in only about 2% of its earnings, while iron ore — the company’s main commodity ⁠— accounts for almost 60%.

Argyle was Australia’s first large-scale diamond operation, pioneering the fly–in fly–out model, and seen as an opportunity for a workforce drawn from across the nation.

It also triggered the creation and adoption of new technology and exploration methods to make the search for diamonds more efficient across the rugged and remote Kimberley landscape.

At its peak, Argyle churned out 40% of the world’s diamond output, which made it the biggest producer by volume.