The world’s biggest diamond mine — famed more for the fistful of coveted pink and red gems it yields each year than being a major producer of lower-quality stones — is being shuttered by Rio Tinto Group after almost four decades. Rivals from Russia to Canada hope that can help turn around the beleaguered industry.
Rio’s Argyle mine in remote Western Australia has transformed the sector since 1983 when the operation began supplying gems for both ends of the market. RBC Capital Markets and Panmure Gordon are among brokers, banks and competitors forecasting the closure could kick-start prices that have waned since 2011, according to PolishedPrices.com, an industry data provider.
Production at Argyle, about 2,600 kilometers (1,600 miles) northeast of the state capital Perth, is scheduled to end before the end of next year after finally exhausting its supply of economically viable stones, said Arnaud Soirat, Rio’s head of copper and diamonds.
“There is going to be a fair bit of supply which is going to come out of the market," Soirat said in an interview Friday at the mine site. “In late 2020 we’ll be stopping operations and will start the rehabilitation of the site."
Argyle is best known as the source of about 90% of the world’s prized pink diamonds — rose-to-magenta hued stones that command among the sector’s highest prices. Sotheby’s auctioned the 59.6 carat “Pink Star", mined by Rio’s rival De Beers, for $71 million in April 2017, a record auction price for any gem. While they attract most attention, the pink stones account for less than 0.01% of Argyle’s total output.
More than three-quarters of Argyle’s output is comprised of lower value brown diamonds, and the mine’s overall output sells for an average of between $15-$25 a carat, Canaccord Genuity Group Inc. estimated in 2017. That’s far less than the $171 a carat average price realized last year by De Beers.
The mine also is the biggest diamond producer by volume and that’s what has put the operation at the center of global oversupply. More than three-quarters of Argyle’s output is comprised of lower-value brown diamonds, and the mine’s overall output sells for an average of between $15-$25 a carat, Canaccord Genuity Group Inc. estimated in 2017. That’s far less than the $171 a carat average price realized last year by De Beers.
A glut of cheap and small diamonds has eroded profits for nearly every miner and made it increasingly hard for the industry’s cutters, polishers and traders to make a profit. In December, some of Rio’s customers refused to buy cheaper stones, while De Beers has been forced to cut some prices and offer concessions to buyers.
Yet, with consumer appetite for diamonds stable, and major mines including Argyle scheduled to shutter, “the rational offset between supply and demand should lead to price growth," Stornoway Diamond Corp. Chief Executive Officer Pat Godin said in March. Declining output, led by Argyle’s closure, will help revive prices, Toronto-based producer Mountain Province Diamonds Inc. said in May.
About 21 million carats a year of global diamond production — including about 14 million a year from Argyle — are scheduled to exit the market by 2023, a volume that’ll only partially be offset by the addition of new mines, according to Russia’s Alrosa PJSC, the world’s diamond biggest producer. The shortfall between annual demand and supply could be between 11 million and 35 million carats by 2023, the company said in a presentation last month.
“In terms of the pink diamonds, the impact is going to be even more dramatic" from Argyle’s closure, Rio’s Soirat said in the interview. “You can imagine the laws of supply and demand will apply, and you can imagine the impact that will have on those very rare pink, red, blue and purple diamonds."
The producer estimates Argyle has only about 150 colored diamonds of sufficient quality left to extract and make available for its annual tender, a sale to invited buyers that showcases 50-to-60 of the year’s most valuable gems, he said.