Bleu Royal diamond makes $43.8m

The 17.61 carat, pear-shaped Bleu Royal diamond, set in a ring, fetched $43.8m. Part of a private collection for 50 years, it was the first time the Bleu Royal was sold at an auction. "This diamond is amongst the rarest to have been unearthed," Christie's said three fancy vivid blue diamonds over 10 carats have appeared for sale in its 250-year auction history, in 2010, 2014 and 2016. The 14.62 carat Oppenheimer Blue sold for over $57m in 2016