A Jewel from the Depths: The "Mediterranean Blue" Unveiled by Sotheby’s

The "Mediterranean Blue" Diamond: A Rare Gem at Auction in Geneva

On May 13, 2025, the prestigious auction house Sotheby’s will unveil an exceptional jewel in Geneva: the “Mediterranean Blue” diamond. Weighing 10.03 carats, this Fancy Vivid Blue diamond is estimated at around $20 million. Its mesmerizing color and impressive size make it an extraordinary rarity on the auction market.

A Shade Inspired by the Mediterranean Sea

The name “Mediterranean Blue” evokes the depth and clarity of the Mediterranean waters. This unique hue is attributed to traces of boron in the diamond’s crystal structure—a phenomenon that also gives the gem rare electrical conductivity. Fewer than 0.5% of all diamonds are classified as Type IIb, a rare category to which this exceptional stone belongs.

A Masterpiece from the Cullinan Mine

The “Mediterranean Blue” was discovered in 2023 in South Africa’s renowned Cullinan Mine, famed for producing some of the world’s most iconic diamonds. Originally weighing 31.94 carats, the rough stone underwent over a year of study and six months of expert cutting to reveal its modified cushion brilliant shape. The result is a gemstone graded VS2 for clarity by the Gemological Institute of America (GIA).

 A Global Showcase Before the Sale

Before its grand unveiling in Geneva, the diamond will be on display in Abu Dhabi starting April 8, 2025, as part of an exhibition hosted by the Bassam Freiha Foundation. This marks Sotheby’s first public event in Abu Dhabi since 2009—offering collectors and art lovers a rare chance to view the gem up close before it hits the auction block.

A Landmark Moment in High Jewelry

The sale of the “Mediterranean Blue” is part of a prestigious series of auctions held by Sotheby’s in Geneva, a city recognized as a global hub for luxury jewelry. This extraordinary diamond joins the ranks of other legendary stones brought to market by the esteemed auction house, further reinforcing its legacy of excellence in high jewelry.

Learn more:
https://www.naturaldiamonds.com/historic-diamonds/sothebys-mediterranean-blue-diamond