Rio Tinto sells last Argyle diamonds at record highs

Rio Tinto’s (ASX, LON, NYSE: RIO) last pink, red, blue and violet diamonds from its iconic Argyle mine, in the remote east […]
There were 41 lots of carefully curated Argyle blue and violet diamonds in Rio Tinto’s 2021 Once in a Blue Moon Tender collection. (Image courtesy of Rio Tinto.)

Rio Tinto’s (ASX, LON, NYSE: RIO) last pink, red, blue and violet diamonds from its iconic Argyle mine, in the remote east Kimberley region of Western Australia, smashed records on Thursday.

Mining ended at Argyle in November 2020, 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.   

While pink diamonds became Argyle’s signature, the mine sporadically produced small blue and violet diamonds that, with the operation now closed, will be extremely unlikely to see in a collection again, according to experts. 

Rio Tinto’s entire 2021 “Once in a Blue Moon" tender collection of 24.88 carats of blue and violet diamonds held in 41 lots was won by a single bidder, the Hong Kong fancy coloured diamond specialist, Kunming Diamonds. 

“We cherish becoming the custodians of the final Australian treasures from this iconic and industry-defining mine and look forward to unearthing the incredible possibilities in the years to come," Kunming Diamonds executive director, Harsh Maheshwari, said in a statement. 

The other collection, made up of 70 rare pink and red diamonds, attracted a record 600-plus bids from ten countries, said Rio Tinto. 

The company, which keeps bids and values under wraps, revealed that the 2021 collection continued its trajectory of “double-digit price growth” with 19 successful bidders from nine countries. The miner noted that overall prices for Argyle’s signature pink diamonds have more than tripled since 2000.  

This article first appeared on

Rio Tinto sells last Argyle diamonds at record highs
2021 “Hero Diamonds” (Image courtesy of Rio Tinto.)

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. 

Its closure removed about 75% of Rio’s diamond output, yet the impact on the miner’s earnings has been negligible. Diamonds bring in only about 2% of the miner’s earnings, while iron ore — its main commodity ⁠— accounts for almost 60%. 

Rio’s minerals boss Sinead Kaufman said despite Argyle mine is no longer producing diamonds, the company will retain the Argyle Pink Diamonds brand. 

“We are extremely proud of the Argyle Pink Diamonds business and its legacy will continue as we retain and manage the brand through a proprietary Argyle pink diamonds trading platform, certification processes and creative collaborations with our trusted partners,” Kaufman said. 


Your email address will not be published.