The world's largest diamond 'Cullinan' at 3106.75 carats and weighing 603.27 gm was found at the Premier Mine in South Africa on January 25, 1905. Named after the mine's owner, Thomas Cullinan, the diamond was sold to Transvaal provincial government, which later gifted it to Britain’s King Edward-VII. Cullinan's polished pieces are now on display in the Tower of London.