The wheel of history will have turned full circle if we go back to firing smelters with wood. That seems unthinkable considering the vast volumes of iron and aluminium that currently use fossil fuels directly or indirectly. However the fuels may run out before the ores. I note the article avoids tackling several 'closing the loop' type issues that arise with uranium mining. A recent proposal to send concentrate to a low wage country rather than local processing seems to be a case of 'value subtracting'. Whether mining can ever be truly sustainable is a moot point but I agree we should try to reduce the negative aspects.

I'd be very pleased to see the CSIRO report that estimates 14% of Australia's electricity demand is for crushing rocks and that it's done in an inefficient way. Google didn't find it for me.

As our coal-fired electric generators are themselves profligately wasteful, spewing over 60% of the thermal energy from burning coal into the air, wasted electricity is a large compounded waste and may represent a great entrepreneurial opportunity.

Taswegian, the carbon referred to is not "firing smelters with wood" but preparing small pellets of ore and black (high-purity) carbon for a new smelting process representing a drastic reduction in total energy consumption and carbon emissions. Charcoal can be suitably pure; coal from the ground rarely is. It might be "full circle" in a poetic sense but it's not a return to medieval technology :-)