Vibranium is a fictional metal, first appearing in the Marvel Comics universe in an issue of *Daredevil* (1966).
Vibranium is one of the many fictional metals featured in the Marvel Comics universe. Two main varieties exist, Wakandan and Antarctic.
Wakandan Vibranium absorbs the vibrations and kinetic energy of other metals. The energy absorbed is stored within the bonds between the molecules that make up the substance. As a result, the more energy vibranium absorbs the tougher it becomes. This variety is also a powerful mutagen, and may enhance mystical powers.
The Antarctic variety is better known as Anti-Metal. This isotope is native to the Savage Land in Antarctica and produces produces vibrations of a specific wavelength that breaks down the molecular bonds in other metals (including adamantium), causing them to liquefy.
Captain America's shield is known to be an alloy containing vibranium.