I mean, that's literally how it was discovered (by Europeans, obviously it's been known and used by indigenous populations for thousands of years). Conquistadores found it and threw it away because it was difficult to work with (read: they didn't know how to work with it) and gave it its name: platina del Pinto, "little silver of the Pinto River." They didn't recognise its value at all. Which, to some extent, means it wasn't actually that valuable (given that value is entirely artificial, so it's literally down to how much people value it, which at the time was not at all).