From sparkling multi-million-dollar diamonds to custom designs, here are the most expensive diamond rings in the world that ...

The extremely rare, 10-carat Mediterranean Blue diamond could fetch a whopping $20 million at Sotheby's High Jewelry auction ...

Fashioned from a 31.94-carat rough diamond discovered at South Africa’s famed ... at Sotheby’s High Jewelry Sale in Geneva on May 13. Given the rarity of Fancy Vivid Blue diamonds ...