Contrary to common belief, emeralds can be more valuable than diamonds when they are of very high quality.
The real color of gold is yellow and any other color means the gold is not completley pure.
The Star of Asia is one of the largest sapphires known in the world, and is currently housed at the Smithsonian Museum of Natural History.
All the gold ever mined in the history of the world can be compressed into an 18-yard cube, roughly 1/10 of the Washington Monument