Where did the material for Captain America's shield come from?

I know that it is made from vibranium, but I want to know where that originated from.Where did the material for Captain America's shield come from?
The first documented discovery of vibranium was during a human expedition to Antarctica where the vibranium was dubbed "Anti-Metal" due to its unique properties. Vibranium has existed on Earth for over 10,000 years, as a large meteorite of it crashed in Wakanda. This vibranium was of a different variety and absorbed sound instead.Where did the material for Captain America's shield come from?
the first poster is correct but Captain America's shield also contains adamantium and steel



cool info here http://en.wikipedia.org/wiki/Captain_Ame…