On Mon, Dec 08, 2014 at 06:25:07PM +1100, Ian Whitchurch wrote:
> Nickel-iron simply isnt worth going to an asteroid belt to mine.

Nickel & iron aren't, no.  The other heavy elements that tend to
accumulate along with them very likely are, though.  On terrestrial
planets, almost all of those end up in the rather inaccessible
metallic core.  Our mines on the surface of Earth just tap the tiny
traces of what was left over after the rest sank.

- Tim