Fictional materials

Kryptonite is a fictional material that appears primarily in Superman stories published by DC Comics. In its best-known form, it is a green, crystalline material originating from Superman's home world of Krypton that emits a unique, poisonous radiation that can weaken and even kill Kryptonians. Kryptonite radiation can be transmitted through any element except lead. There are other varieties, such as red kryptonite and gold kryptonite, which have different but still generally negative effects.

Neutronium (or element zero) is a hypothetical substance made purely of neutrons. The word was coined by scientist Andreas von Antropoff in 1926 (before the 1932 discovery of the neutron) for the hypothetical "element of atomic number zero" (with no protons in its nucleus) that he placed at the head of the periodic table (denoted by -).

paranormal phenomenon

Adamantium is a fictional metal, most famously appearing as an alloy in American comic books published by Marvel Comics. It is best known as the substance bonded to the character Wolverine's skeleton and claws. It also appears in the 1941 story "Devil's Powder" by Malcolm Jameson.

Vibranium () is a fictional metal appearing in American comic books published by Marvel Comics, noted for its extraordinary abilities to absorb, store, and release large amounts of kinetic energy. Mined only in the kingdom of Wakanda, the metal is associated with the character Black Panther, who wears a suit of vibranium, and Captain America, who bears a vibranium/steel alloy shield. An alternate form of the material, known as Antarctic Vibranium, or Anti-Metal, has appeared in the Savage Land.

Unobtainium (or unobtanium) is a term used in fiction, engineering, and common situations for a material ideal for a particular application but impractically difficult or impossible to obtain. Unobtainium originally referred to materials that do not exist at all, but can also be used to describe real materials that are unavailable due to extreme rarity or cost. It can also be used to refer to a device rather than a material.

fictional chemical substance

Computronium is a material hypothesized by Norman Margolus and Tommaso Toffoli of the Massachusetts Institute of Technology (MIT) in 1991 to be used as "programmable matter", a substrate for computer modeling of virtually any real object.

fictional material in Star Trek

thumb|The fictional ice-nine is depicted as being capable of causing any liquid water to permanently freeze unless heated far above room temperature. Ice-nine is a fictional material that appears in Kurt Vonnegut's 1963 novel ''Cat's Cradle''. Ice-nine is described as a polymorph of ice which instead of melting at 0°C (32°F) melts at 45.8°C (114.4°F). When ice-nine comes into contact with liquid water below 45.8°C, it acts as a seed crystal and causes the solidification of the entire body of water, which quickly crystallizes as more ice-nine. As humans are 55-60% water, ice-nine kills nearly i

Thiotimoline is a fictitious chemical compound conceived by American biochemist and science fiction author Isaac Asimov. It was first described in a spoof scientific paper titled "The Endochronic Properties of Resublimated Thiotimoline" in 1948. The major peculiarity of the chemical is its "endochronicity": it starts dissolving before it makes contact with water.

Urban legend