Rio Tinto has marked the end of production at its Diavik diamond mine in Canada’s Northwest Territories, concluding more than two decades of operations that yielded over 150-million carats of rough diamonds.
Diavik, located about 220 km south of the Arctic Circle beneath Lac de Gras, was discovered in 1991 and began production in 2003.
The operation, comprising four kimberlite pipes, used both openpit and underground mining methods and produced predominantly white gem-quality diamonds, along with a smaller proportion of rare yellow stones.
Rio Tinto Iron and Titanium and Diamonds MD Sophie Bergeron said mining at Diavik displayed decades of innovation and perseverance.
“Forty years ago there were very few people who believed there were diamonds in Canada – even fewer could have foreseen how the Diavik story would unfold. To arrive at this milestone has required vision, courage and determination to overcome significant challenges to mine diamonds beneath a frozen lake in one of the world’s most remote and pristine ecosystems.”
Diavik COO Matthew Breen described the closure as a significant moment for the region.
“This is an historic day for Diavik and the Northwest Territories and a great source of pride for this unique Canadian success story. Diavik has been an inspired collaboration between a modern mining company and Indigenous partners with an enduring legacy of socioeconomic benefits for the North.”
The end of production was marked by a ceremony attended by Indigenous government organisations, government representatives and other stakeholders.
Rio Tinto said closure planning for the mine had been in place since before production began, with rehabilitation activities set to continue until 2029, followed by a period of post-closure monitoring.
The company added that final production from Diavik will continue to be processed, polished and sold through 2026 and beyond via its global customer network.