There is a lot more that goes into mining costs than the routine weekly costs during production. All that equipment does not show up magically by itself. How about exploration costs, permitting costs, metallurgical testing costs? And environmental costs.....all those nasty tailings have to go somewhere, be controlled, and what about reclamation? Water? Lease costs? Royalties. And yes, management, marketing, benefits, and on and on.
And of course.....you left out the actual mining costs.
All that, with no exploration other than surface grabs, no true feasibility, no reserves.
But never mind all that.....Mexus management claims $150/oz production costs, and they are experienced miners, right? Mining is so darned easy! Blast it, leach it in a big old vat, and gold pours out the other end.