Geneva — An exceptionally rare blue diamond went under the hammer in Geneva Tuesday, selling for almost $44 million, making it one of the most expensive diamonds ever sold at auction, Christie’s said. Weighing 17.61 carats, the Bleu Royal is the largest internally flawless fancy vivid blue gem ever to appear for sale in auction history.

It was the star lot in a series of luxury sales in Geneva this month, which also featured items from film history including pearls worn by Audrey Hepburn and Marlon Brando’s self-engraved watch.

The Bleu Royal had been expected to fetch between $35 million