As we can see on this page by Jack Kirby, the pieces being collected appear to be some kind of technology. It seems as if Kirby intended the Vibranium meteor to not be a meteor at all, but rather a crashed alien ship mistaken for a meteor. Now I realise the idea that the Wakandans were always super duper smart scientists who put everyone else to shame for centuries was a retcon, clearly T'Challa did not have to study abroad if that was always the intention, but they were always depicted as being ahead. And with or without the retcon, it still explains why they are so far ahead.
Now if anyone could actually identify which alien civilization they copied their tech from...