"Cobalt and rare earth elements are in the tank, forget them (except as by products)."

You are probably correct about this for the time being.  That does, however, bring up an interesting question. 

Let's say that production drilling begins (I know that this is a ways off.) for copper, gold, or silver.  Since all of these metals, and the elements above as well as others, will be brought up at the same time, what happens to the ones that aren't in favor by the market at that time?  Do they typically get processed and placed in a warehouse until more favorable market conditions arrive or do they just sell them for the best price they can get to give better current cash flow and in order to cut back on storage costs?