Adamantium

"Adamantium? Well, it never appeared in my favorite game called Minecraft. Now I can sense it was found in a futuristic place. Now Team RWBY just hit the jackpot for this! Well, I think it appeared in my favorite Marvel comic books. I hope this thing works."

--Su Ji-Hoon, Adamantium Rush

Adamantium is a fictional metal alloy appearing in American comic books published by Marvel Comics. It is best known as the substance bonded to the character Wolverine's skeleton and claws. 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 the stories where it appears, the defining quality of adamantium is its practical indestructibility.

Etymology
The word is a pseudo-Latin neologism (real Latin: adamans, adamantem [accusative]) based on the English noun and adjective adamant (and the derived adjective adamantine) with the neo-Latin suffix "-ium." The adjective has long been used to refer to the property of impregnable, diamondlike hardness, or to describe a very firm/resolute position (e.g. He adamantly refused to leave). The noun adamant has long been used to designate any impenetrably or unyieldingly hard substance and, formerly, a legendary stone/rock or mineral of impenetrable hardness and with many other properties, often identified with diamond or lodestone. Adamant and the literary form adamantine occur in works such as Prometheus Bound, the Aeneid, The Faerie Queene, Paradise Lost, Gulliver's Travels, The Adventures of Tom Sawyer, The Lord of the Rings, and the film Forbidden Planet (as "adamantine steel"), all of which predate the use of adamantium in Marvel's comics.