Known as the Mellon Blue, the 9.51-carat fancy vivid blue diamond is graded internally flawless and is mounted in a ring. Christie’s has given the stone a presale estimate of around USD 30 million (AUD 45.7 million).
The diamond has notable provenance. It once formed part of a pendant owned by Rachel Lambert Mellon, the American horticulturist, philanthropist, and art collector whose grandfather Jordan Lambert invented Listerine. Mellon’s landscape designs include the celebrated gardens at the White House.
The Mellon Blue last appeared at auction in 2014, when Sotheby’s sold it for USD 32.6 million, setting a world record at the time for a blue diamond. Ahead of its Geneva sale, Christie’s plans to preview the stone in Saudi Arabia, Shanghai, Hong Kong, Bangkok, and New York.
