Petra Sells 2 Big Diamonds Into Partnership With Stargems for $14M
The 342.92-carat rough white diamond and the 18.30-carat rough blue diamond will be cut and polished in South Africa.

According to the miner, a 342.92-carat Type IIa white diamond and an 18.30-carat Type IIb blue diamond, both of which were recovered at the Cullinan mine in South Africa, have been sold into the partnership.
Petra said it will receive an upfront payment of $10 million for the former and $3.5 million for the latter.
This comes to about $29,161 per carat for the rough white diamond and about $191,257 for the rough blue diamond.
Petra will also retain a 50 percent interest in the profit of the polished proceeds for both after costs.
Stargems is the Johannesburg-based subsidiary of vertically integrated diamond company Stargems Group and is a diamond beneficiation licensee, which means the two diamonds will be cut and polished at the Stargems factory in Johannesburg, South Africa.
“These two diamonds are wonderful examples of the very high quality and rare white and blue diamonds that are so well known from the Cullinan Diamond Mine,” said Petra CEO Richard Duffy.
“We are delighted that both stones will be manufactured in South Africa, and it is fitting that we will be working with Stargems, who specializes in the sourcing and supply of the finest diamonds to customers across the world.”
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