The Oppenheimer Blue sold on Wednesday for more than $57.5 million including fees at a Christie's auction in Geneva, making it the most expensive diamond ever sold.

While flawless diamonds are considered the most valuable, they are also rare, so don’t count out diamonds with small inclusions when making a purchase. “Most inclusions are microscopic ...

The most expensive diamond in the world costs US $250 million.

The most valuable black opal features bright red stone against a very black base. In the '80s and '90s, gem-quality brown diamonds were worth about $1,500 per carat, but now many sell for up to $ ...

Aging sets, like those from the Diamond & Pearl era, are becoming increasingly desirable, but are very difficult to find. Trainers run the show with some of the most valuable Ultra Prism cards.