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.
Sergio (carbonado)
Sergio (Portuguese: Carbonado do Sérgio) is the largest carbonado and the largest rough diamond ever found. It weighed and was found above ground in Lençóis (State of Bahia, Brazil) in 1895 by Sérgio Borges de Carvalho. Like other carbonados it is believed to be of meteoritic origin.