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.
Koh-i-Noor Hardtmuth
At the 1889 World Fair in Paris, the Hardtmuth's displayed their pencils rebranded as "Koh-I-Noor Hardtmuth". Each pencil was encased in a yellow cedar-wood barrel. The inspiration for the name was the famous Koh-i-Noor diamond (Persian for "Mountain of Light"), part of the Crown Jewels of the United Kingdom, and the largest diamond in the world at the time.