One of the problems is that we've virtually eliminated hard rock mining in the USA. Environmental concerns are a major factor.
They mention platinum. I've panned platinum out of the Trinity River in California, while panning for gold. It's there, and the mother deposits are there, too. But you'd never be able to mine the stuff.
We have huge copper reserves, but the cost of mining, given the environmental restrictions, makes it impractical. So we get it from Africa now, for the most part.
when it comes to extracting metals from the earth we literaly have only scratched the surface.
"we're all gonna die" bump,LOL
Did you know some American Indian tribes used to throw Platinum back into the rivers because they thought it was godl that wasn't "ripe" yet? Just a little trivia on the subject!