An unusually large pink diamond sold for a record-breaking $50 million (about 50.3 million Swiss francs) Tuesday at Christie's auction house in Geneva.

After five minutes of bidding, the 18.96-carat Pink Legacy became the world record holder for price paid per carat for a pink diamond at auction. Christie's international head of jewelry, Rahul Kadakia, said it was purchased by American luxury brand Harry Winston, and will be renamed the Winston Pink Legacy.

"You have to acknowledge first that the Pink Legacy diamond was a very special diamond," Kadakia said. "It is one of the best and finest examples of pink diamonds at this size and color and it proved it with a new world record price per carat."

Pink Legacy is categorized as a "Fancy Vivid" diamond, the highest grade of color intensity. Only 1 in 100,000 diamonds receives the grading.