After being retrieved, the diamond was transferred to Antwerp where it underwent acidisation and provisional analysis. Test results proved it to be a 478 carat diamond of type II D colour, the highest colour grading available for a white diamond. It was also noted to have outstanding clarity with zero inclusions visible in its rough form. It also holds potential to yield one of the largest flawless D colour round polished diamonds in history.

Speaking on the discovery Clifford Elphick, Chief Executive Officer of Gem Diamonds, added: “Preliminary examination of this remarkable diamond indicates that it will yield a record breaking polished stone of the very best colour and clarity. With a further 45 years of life remaining, we expect Letšeng to make history for many years to come.”

The discovery is the third significant recovery from the Letšeng Mine, following the recovery of 603 carat Lesotho Promise in 2006 , the 493 carat Letšeng Legacy in 2007 and the 601 carat Lesotho Brown in 1960. This makes the Letšeng Mine a part of historic discoveries with four of the 20 historic diamonds of the world, recovered from the mine.

Minister Monyane Moleleki, the Minister of Natural Resources for Lesotho said: “Once again Letšeng has proved its ability to produce extraordinary diamonds and continues to place Lesotho at the forefront of diamond producing countries. We will continue to proudly develop this asset and the rare diamonds that it produces to their maximum value for the benefit of the people of Lesotho.” Gem Diamonds is a FTSE 250 listed diamond company.