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.
Spirit of de Grisogono Diamond
The Spirit of de Grisogono is the world's largest cut black diamond and the world's fifth largest diamond overall. Starting at an uncut weight of , it was taken from its origin in western Central African Republic and cut by Swiss jeweler De Grisogono. The resulting mogul-cut diamond weighs and is set in a white gold ring with 702 smaller white diamonds totaling . The ring is said to have been sold.