An exceptional blue diamond weighing 17.61 carats, described as the largest internally flawless fancy vivid blue diamond to appear at auction, is up for grabs at Christie’s Geneva in November.

Cut and polished into a perfectly symmetrical pear combined with a rich vivid blue colour and flawless purity, the “Bleu Royal” diamond has a pre-sale estimate of US$35 million to US$50 million. According to Christie’s, the diamond is among the rarest to have been unearthed and has remained part of an important private collection for the past 50 years. 

“This is a true miracle of nature,” commented Rahul Kadakia, Christie’s International Head of Jewellery. “Over our 257-year long history, Christie’s has had the privilege of offering the world’s rarest gems at auction, and Bleu Royal continues this tradition. We are proud to offer collectors the opportunity to own a diamond fit for royalty.”

Driven by collector demand and an increasingly limited supply, prices for top-quality fancy colour diamonds have increased exponentially in recent years. In the saleroom, fancy vivid blue diamonds over 10 carats are virtually unheard of — in more than 250 years of auction history at Christie’s, only three such stones have ever appeared for sale: The Bulgari Blue at 10.95 carats, which sold for US$15.76 million in 2010 in New York; The Winston Blue at 13.22 carats, which fetched US$23.8 million in 2014 in Geneva; and The Oppenheimer Blue at 14.62 carats, which was snapped up for US$57.54 million in 2016 in Geneva.

Christie’s Magnificent Jewels auction is scheduled for November 7, 2023 in Geneva.