Adamantium is a fictional metal alloy appearing in American comic books published by Marvel Comics, and is best known as the substance bonded to the character Wolverine's skeleton and claws. Within Marvel Comics stories, adamantium is a group of man-made metal alloys of varying durability. Adamantium was created by writer Roy Thomas and artists Barry Windsor-Smith and Syd Shores in Marvel Comics' Avengers #66 (July 1969), which presents the substance as part of the character Ultron's outer shell. In all stories where it appears, the defining quality of adamantium is its practical indestructibility.

So, in the Marvel universe, adamantium is rarely used due to its high cost, lack of source materials and inability to be manipulated easily.

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