Esh, Interesting article along the theme ... note the reference...

Esh, Interesting article along the theme ... note the reference to commodity shortages, and price spikes. The supply of long term metal to the market is going to be severely curtailed by the lack of commercially significant discoveries over the last decade, and the lack of money being spent on exploration now. Might make a mess of the predictions? esp Cu, Ni,
https://www.ft.com/content/f65ee896-9cfb-11e6-8324-be63473ce146?mhq5j=e2