Reports say that Petra Diamonds is considering owning another 37-percent share in the Cullinan mine in South Africa for $80 million. This would take its current share holding in the mine to 74 percent. Two years ago, Petra bought the mine along with Saudi bank Al Rajhi, from De Beers, for a value of $125 million. The remaining mine holding is owned by a group representing local mine workers, reports say.

The mine has has been the source of the largest diamond to be found – the 3,100-carat Cullinan diamond adorning the British Crown Jewels. Recently, Petra announced the discovery of an egg-shaped 507-carat diamond of exceptional colour and clarity. The value of the diamond, as per media reports is $20 million. Also, discovered at the mine were two gems – one 58 carats and the other 53 carats, which Petra sold for a higher-than-expected $2.8 million.

Petra plans to finance the deal by raising $100 million through placement of new shares.