Christie's has auctioned off the famed Archduke Joseph Diamond for $21,474,525 including commission, a world auction record price per carat for a colorless diamond. The price was well above the expected $15 million and more than triple the price paid for it at auction almost two decades ago. The auction took place in Geneva. The 76.02-carat diamond, with perfect color and internally flawless clarity, came from the ancient Golconda mines in India. It was named for Archduke Joseph August of Austria, the great grandson of both a Holy Roman emperor and a French king.