A massive 478 carat diamond has been found at the Letseng Mine, owned by Gem Diamonds, in Leotho, Africa. The diamond, said to have a flawless center, could produce a 150-carat round cut white diamond. If true, this would be the largest polished diamond ever found. The current largest cut diamond is the Kohinoor, weighing in at an astonishing 105 carats. The largest rough diamond found was the Cullinan, which weighed 3,106 carats uncut.