Mediterranean blue diamond expected to fetch $20 million at auction

A ten-carat blue diamond, dubbed the "Mediterranean Blue Diamond," is expected to fetch $20 million at auction. Sotheby's unveiled the gem in Geneva, Switzerland, ahead of the sale later this month. The cushion-cut stone was mined in South Africa and boasts a rare, vivid blue hue. The diamond was discovered in South Africa in 2023 and studied for over a year. The rough diamond initially weighed over 30 carats. After a meticulous six-month planning and cutting process, the Mediterranean Blue was shaped into a modified brilliant cushion. Blue diamonds are increasingly rare, representing only 0.1% of all diamonds found. The Cullinan mine, where this diamond was discovered, is renowned for producing some of the world's largest diamonds. These include the "Great Star of Africa" and the British Royal Family's Cullinan diamond.