KCN:ASX has a 0.3g/t cut-off and 0.6g/t average grade, from a...

KCN:ASX has a 0.3g/t cut-off and 0.6g/t average grade, from a 120koz 6-7mtpa regular plant.

So 0.15g/t cut-off could in effect mean 0.3g/t average grade.

If heap leach or sorting work fine (and are cheaper than a regular plant), then 0.15g/t cut-off might be realistic.

So it's a matter of selecting the cut-off and scale that is most profitable.

Is 0.15g/t cut-off and 10mtpa profitable? If so, go with huge pits.
If not, is 0.25g/t cut-off and 6mtpa profitable? If so, go with medium pits - the reserve would be say 30% smaller, so plant MTPA would likely be smaller to match.
If above is not profitable, then is 0.35g/t and a small plant profitable (eg. RPM only)?




For Fort Knox to have 0.1g/t cut-off, I'm assuming they have a quite huge scale. Enough to have cost efficiencies to profit from huge amounts of low grade ore. 'Valley Heap Leach' from memory. Filling the whole Valley with tarps and ore.

I think it's >200-500koz PA and 16 MTPA.