Comment by whiskers08xmt

A lot of heavy rare earth metals can only be found in very limited concentrations in the earth's crust, with the largest concentrations all being from asteroid impacts. As a consequence, these metals are incredibly valuable. A single high-concentration asteroid, could provide more of these metals than has been mined in the history of the earth, in high concentrations, and may be able to make a host of applications economically viable, which previously weren't.