Cullinan Diamond
The Cullinan Diamond is the largest gem-quality rough diamond ever found, weighing , discovered at the Premier No. 2 mine in Cullinan, South Africa, on 26 January 1905. It was named after Thomas Cullinan, the mine's chairman.
Black, Starr &amp; Frost
2012: Black, Starr & Frost sold the Archduke Joseph Diamond, a 76-carat, D-color, internally flawless diamond, the largest D color internally flawless Golconda diamond in the world for $21.5 million at Christie’s Geneva Magnificent Jewels auction, setting three world records for the sale of a colorless diamond.