Moussaieff Red Diamond ($7 million) Once known as the Red Shield Diamond, the Moussaieff Red is the largest Fancy Red diamond in the world at 5.11 carats. Discovered in Brazil in the 1990s, the diamond has a triangular brilliant cut (also known as a trilliant cut) and was most recently displayed at the 2003 "Splendor of Diamonds" exhibit at the Smithsonian.
Sun-Drop Diamond ($10.9 million) Setting a record for a yellow diamond at auction, the Sun-Drop Diamond of South Africa sold at Sotheby's Geneva this week for more than $10.9 million. The pear-shaped gem weighs 110.3 carats and was discovered only last year, meaning it has no previous owners, which added to its value. And it also comes with a bonus—the new owner gets to name the stone.