Cobalt Price, page-26

Apart from what is stockpiled, there is some debate that it might not be economic to dig, sort crush and ship. Some of the more mining experienced posters came up with costs in the US$70-80 range (Happy to be corrected), so we would need to sell it at a rate somewhere above that to justify allocating the capital.

If we find more Pollucite and have to dig up the Microcline as a by product, then that helps a lot.

But, as usual, the details from Dave are a bit sketchy.