RAPAPORT... Petra Diamonds has sold a 299.3-carat rough stone to Stargems for $12.18 million, after recovering the diamond at its Cullinan mine in South Africa earlier this year.The "exceptional" white, type IIa, gem-quality diamond fetched $40,701 per carat, exceeding the $34,386 per carat Petra achieved for the 424.89-carat Legacy of the Cullinan Diamond Mine in May 2019, the company said Friday. The buyer was Stargems DMCC, the Dubai unit of the international diamond sourcing and supply company.The transaction comes on the back of Petra's recent sale of the Letlapa Tala collection of blue rough diamonds - also from Cullinan - to De Beers for $40.4 million."This is another significant sale for Petra Diamonds, following the sale of the Letlapa Tala collection in November 2020, and a further endorsement of the quality of the Cullinan ore body, which is known for its exceptional stones," said Petra CEO Richard Duffy.The miner found the 299-carat stone in January at Cullinan's C-Cut area, a high-value extension to the deposit. Image: The 299-carat stone. (Petra Diamonds)