RAPAPORT… Rio Tinto wants to buy a 60% stake in the Star-Orion South diamond exploration site in Canada for CAD 70.5
million ($53.3 million), according to project owner Star Diamond Corp.
In 2017, Rio Tinto entered into a joint-venture deal under which it had the right to acquire shares in the proposed mine. Its decision to opt in fully to the project comes five years earlier than the original deadline outlined in the agreement. Star Diamonds is currently reviewing a notice it received from Rio Tinto stating its intentions, it noted Friday.
Star-Orion South has an indicated mineral resource of 55.4
million carats of rough, estimated at $210 per carat, Star Diamond said. The
deposit also contains inferred resources of 11.5 million carats in its Star and
Orion South kimberlites. A major study of goods at the project, conducted in
March, indicated nearly 27% of diamonds at its Star project and 13% of those at
the Orion South kimberlite are type IIa.
Rio Tinto owns two other diamond projects. Its Argyle mine,
in Australia, is set to close in 2020, while the Diavik deposit, in Canada’s
Northwest Territories, is due to produce its last diamonds in 2025.
Star Diamonds’ stock price soared 49% Friday following the
announcement.
Image: The Star-Orion South site. (Star Diamond Corp.)
Rio Tinto Seeks Majority Stake in Canada Site
The Bottom Line
- Rio Tinto aims to purchase a 60% stake in Star-Orion South for CAD 70.5 million ($53.3 million), moving up its acquisition timeline.
- Star-Orion South holds an indicated mineral resource of 55.4 million carats valued at $210 per carat, with additional inferred resources of 11.5 million carats.
- Rio Tinto’s existing diamond operations include the closing Argyle mine in Australia (2020) and the Diavik mine in Canada, which will cease production by 2025.
Summary by Rapaport AI
More Stories

Qatar Diamond Exchange to Collaborate with Italian Bourse
Parties signed MoU to extend connection among their members, broaden cooperation and advance commercial relationships.

China Signs Deal to Reinvigorate Interest in Natural Diamonds
Shanghai Diamond Exchange hosts signing of Beijing Declaration, with government representatives from Botswana, Namibia and South Africa.

AI, Gen Z Are Hot Topics at AGS Conclave
This year’s edition is last to take place in September, as event returns to spring in 2027.
