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.
Canadian diamonds
Located approximately 190 miles north of Yellowknife, the Diavik Diamond Mine is one of the largest open pit diamond mines in the world (according to production) and currently produces around 8 million carats annually. The mine is currently in a transitional shift from open pit to underground mining, and the life span of the mine is expected to be 16 to 22 years from its opening in 2003.