507 carat diamond found in Cullinan Mine

Petra Diamonds has unearthed one of the world's 20 largest, high-quality white diamonds at the Cullinan mine in South Africa.

The 507.55 carat diamond, found on September 24, could be worth about $US20 million.

It is in these early stages described of exceptional colour and
clarity.Also discovered near were other large white diamonds of 168
carats, 58.50 carats and 53.30 carats.

Cullinan Mine is also known for the discovery of the world's largest gem diamond ever recovered, at 3,106 carats rough.