$39 million return for beautiful blue diamond

A stunning blue fancy colour diamond was the headline act at a recent Christie’s auction in Geneva, commanding a remarkable return.

The 9.51-carat Mellon Blue hit the auction block at the 11 November Magnificent Jewels sale and returned $USD25.6 million ($AUD39.24 million).

Set in a ring, the diamond is internally flawless and was once owned by Rachel Lambert Mellon, a horticulturist, philanthropist, and art collector. Mellon’s grandfather, Jordan Lambert, was the inventor of Listerine.

The final price landed within the pre-sale range; however, it represented a notable 20 per cent decline from its most recent sale, which occurred in New York in 2014. At the time, the Mellon Blue was mounted in a pendant and was purchased by a Hong Kong buyer for $USD32.6 million ($AUD49.97 million).

Max Fawcett, Christie’s global head of jewellery, said that the sale reflected a “market defined by confidence and discernment.”

The auction house noted that this was the third-highest price achieved by a vivid blue fancy colour diamond sold at Christie’s. The Oppenheimer Blue (14.6-carats) was sold for $USD57.5 million in 2016, and the Bleu Royal (17.6-carats) was sold for $USD43.8 million in 2023.