Phoenix jeweler Alfredo J. Molina set a world record for the sale of a diamond.

Christie’s auctioned off Molina’s Archduke Joseph Diamond for nearly $21.5 million Tuesday night, a world auction record price per carat for a colorless diamond.

The Archduke Joseph Diamond went for $21,474,525 including commission at Christie’s auction. That was well above the expected $15 million and more than triple the price paid for it at auction almost two decades ago. The 76.02-carat diamond, with perfect color and internally flawless clarity, came from the ancient Golconda mines in India.

Molina, owner of Molina Fine Jewelers in Phoenix, said immediately afterward that there were two main bidders and that he was delighted with the result. Molina said the winning bidder, who wished to remain anonymous, is going to donate the diamond for display at a museum.

“It’s a great price for a stone of this quality,” Molina told The Associated Press. “It’s one of a kind, so it’s like saying ‘Are you pleased when you sell the Mona Lisa?’ Or ‘Are you pleased when you sell the Hope Diamond?’ It’s all what the market will bear, and the stone sold for a very serious price.”

Named for Archduke Joseph August of Austria, the great-grandson of both a Holy Roman emperor and a French king, the diamond passed to his son, Archduke Joseph Francis, who put it in a bank vault, then to an anonymous buyer who kept it in a safe during World War II. From there it surfaced at a London auction in 1961, then at a Geneva auction in 1993, when Christie’s sold it for $6.5 million.