"Someone please correct if I am barking up the wrong tree."I suggest you are. The new base cost as you set it out would be 18c, not zero.As I see it.
Week 46 Wrap: Copper hits 2mth low as Trump threatens net zero pace; US rally fades; HotCopper’s picks
AN1 CuFe sells its Crossroads gold royalty to Northern Star for $4M cash; says better than waiting for mine launch