Two rare diamonds have been sold by Petra Diamonds (PDL.L) for a total of $13.5m (£9.8m). 

A 342.92 carat white diamond (previously announced on 28 July 2021) and an 18.30 carat blue diamond, both recovered at the Cullinan Diamond Mine in South Africa, have been sold into a partnership with Stargems. 

Petra said in a release that it will receive an upfront payment of $10m for the 342.92 carat stone and US$3.5m for the 18.30 carat stone, as well as retaining a 50% interest in the profit uplift of the polished proceeds of both diamonds, after costs.

“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 Richard Duffy, CEO of Petra. 

"We are delighted that both stones will be manufactured in South Africa and it is fitting that we will be working with Stargems, who specialise in the sourcing and supply of the finest diamonds to customers across the world.”

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The Cullinan mine earned its place in history with the discovery of the Cullinan diamond in 1905, the largest rough gem diamond ever found at 3,106 carats.

This stone was cut into the two most important diamonds which form part of the Crown Jewels in the Tower of London.

These included the First Star of Africa, which is mounted at the top of the Sovereign’s Sceptre and which at 530 carats is the largest flawless cut diamond in the world, and the Second Star of Africa, a 317 carat polished diamond which forms the centrepiece of the Imperial State Crown.

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