De Beers recently sold its Cullinan Diamond Mine in South Africa to the Petra Diamonds Cullinan Consortium for $150 million.

Named after Sir Thomas Cullinan, who discovered the kimberlite deposit in 1898, the Cullinan kimberlite pipe is the largest known pipe in South Africa. It has been mined for nearly a century and has resources for at least 40 more years of production at current production levels, a statement said. It is best known for the discovery of the Cullinan diamond in 1905. At 3,106.75 cts., it is by far the largest gem diamond ever recovered.

The Cullinan Mine has produced more than 300 stones weighing 100-plus cts. and more than a quarter of all diamonds weighing 400-plus cts.