Rio Tinto sells last diamonds from iconic Argyle mine

The Argyle mine, in remote Western Australia, accounted for 90% of worldwide pink diamond production. (Image courtesy of David Gardiner |Flickr Commons. )

Rio Tinto (ASX, LON, NYSE: RIO) has put up for sale its final collection of rare pink, red, violet and blue diamonds from its iconic Argyle mine in the remote east Kimberley region of Western Australia.

Mining ended at Argyle in early November last year, after 37 years of uninterrupted production, during which the mine became the source of about 90% of the world’s prized rose-to-magenta hued stones.

“The number of diamonds presented at the annual Argyle tender over the last 38 years would barely fill two champagne flutes”
Patrick Coppens, general manager, sales and marketing for Rio Tinto’s diamonds business

The 2021 Argyle tender, being showcased in Antwerp, Belgium, is the final collection of diamonds from the final year of mining operations.

“The first Argyle Pink Diamonds Tender was held in Antwerp in 1984 and I am delighted to host the final epic collection in Antwerp,” Patrick Coppens, general manager, sales and marketing for Rio Tinto’s diamonds business said in a media release.

The number of diamonds presented at the annual Argyle tender over the last three decades would barely fill two champagne flutes, Coppens noted, which highlights the rarity of this final collection.

Comprising 70 diamonds weighing 81.63 carats, the 2021 tender has a record number of stones larger than one carat. It includes the Argyle Eclipse, a 3.47-carat diamond that is the largest Fancy Intense Pink diamond ever offered at the event.

The collection, called “The Journey Beyond”, makes reference to 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.

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, located within the ancient Matsu Ranges more than 3,000 km north of Perth, was Australia’s first large-scale diamond operation. It pioneered the fly–in fly–out model, drawing workers 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.