Vibranium is a fictional metal that appears in the Marvel Comics Universe. It is most commonly known as one of the materials used to construct Captain America's shield, but it is also noted for its connection to the Black Panther and his native homeland of Wakanda (a fictional country in Africa). Vibranium was first deposited on Earth by a meteorite 10,000 years ago. The first documented discovery of vibranium was during a human expedition to Antarctica. This particular isotope was dubbed "Anti-Metal" due to its property of dissolving other metals.
A different variety of vibranium found in Wakanda absorbs soundwaves and other vibrations, including kinetic energy. It was discovered by the Wakandan king T'Chaka, father of the Black Panther T'Challa. To protect this resource, he concealed his country from the outside world. T'Chaka funded his country's education by occasionally selling off minute quantities of the metal. As a result, Wakanda is one of the world's most technologically advanced nations.
During the early 1940s, a small amount of Wakandan vibranium came into the possession of the scientist Myron MacLain. He tried to combine vibranium with iron to form a new tank armor, but was unable to fuse the elements. One morning, he found that the two materials had bonded on their own in an unknown manner. The ultra-resilient alloy was used to create Captain America's shield. MacLain worked for decades (without success) to duplicate the accident. However, during an experiment in the 1960s, he developed the virtually indestructible metal adamantium.
When T'Challa became king of Wakanda, he strove to end his country's isolation from the rest of the world. Making the existence of vibranium known to the outside world around the mid-1980s, he sold small quantities of it to foreigners whom he believed would not use it to harmful ends. T'Challa used the profits to enrich and modernize his nation. Over the years, many have tried to obtain or affect the mound of Vibranium at Wakanda, but for the most part Wakanda has kept it safe, and become quite powerful in the process.