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.
Amarillo Starlight
The Amarillo Starlight is the largest diamond found by a park visitor in the Crater of Diamonds State Park in Arkansas since 1972, when it was established as a state park. The Amarillo Starlight was found by W. W. Johnson of Amarillo, Texas in 1975 while he was vacationing at the park with his family. When unearthed, it was a white diamond, but it has since been cut into a marquise shape. Its value has been estimated between $150,000 and $175,000.