When taken to a Fossil Reviver in the games, it will be turned into the Pokemon, Anorith.
Locations:
Ruby & Sapphire: Route 111
Emerald: Mirage Tower
Diamond, Pearl and Platinum: After you get the National Dex, go into the Underground and you will have a chance of finding a Claw Fossil.
Black & White: A man in Twist Mountain will give one of the Fossils randomly to you after you get the National Dex.
Stub!
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