Some notable fictional elements include:

Table of contents

1 Adamantium 2 Kryptonite 3 Mithril 4 Octiron 5 Unobtainium 6 Tiberium

Adamantium

• Description: The strongest metal known in the universe of Marvel Comics.
• Properties: Similar to steel. Once cast, it cannot be bent, blunted, or broken.
• Uses: Weapons, notably Wolverine's claws and various robots.

• Description: During the destruction of Superman's home planet Krypton, much of the planet's crust was transformed into this mineral. It is not related to the real-life krypton gas.
• Properties: Highly radioactive; exposure to it is highly detrimental to Kryptonians (prolonged exposure can also harm Earth-humans).
• Uses: Can be tooled like jade, but is more frequently used as a deus ex machina in world domination plots by people such as Lex Luthor.

• Description: A light, silvery metal.
• Properties: As strong as steel and very light. One may think that mithril is actually some kind of titanium or aluminium alloy.
• Uses: Used for making superb chain-mail armour and other primitive means of protection.

• Description: A dense black metal which is a large part of the Discworld.
• Properties: Highly magical with a melting point above the range of metal forges.
• Uses: Few. The gates of Unseen University are made out of it, which is rather ruined by the fact that most people go 'round the back, and at one point a wizard made a staff out of it, which in the long run turned out to be a mistake.

• Description: Informal name for an improbably strong material found in works of science fiction, such as The Core.
• Properties: Usually metallic in appearance; Possesses properties that are unlikely or impossible for any real material to possess and is hence unobtainable.
• Uses: Typically used to fill a plot hole, allowing characters to do things that may not be physically possible even in principle.