Cullinan Diamond
The Cullinan diamond was found below the surface at Premier Mine in Cullinan, Transvaal Colony, by Frederick Wells, surface manager at the mine, on 26 January 1905. It was approximately long, wide, deep, and weighed . Newspapers called it the "Cullinan Diamond", a reference to Sir Thomas Cullinan, who opened the mine in 1902. It was three times the size of the Excelsior Diamond, found in 1893 at Jagersfontein Mine, weighing . Four of its eight surfaces were smooth, indicating that it once had been part of a much larger stone broken up by natural forces. It had a blue-white hue and contained a small pocket of air, which at certain angles produced a rainbow, or Newton's rings.
Sweet Josephine Diamond
The diamond, which had been owned by an American family for 15 years prior to its 2015 sale, is the largest cushion-shaped diamond classified by the Gemological Institute of America as "fancy vivid" ever to be sold at auction, regardless of color, and it is one of only three "fancy" pink diamonds weighing more than 10 carats to be sold in the previous 250 years.