copper, gold and silver, page-6

horse - you are probably correct in saying that Au and Ag credits are effectively paying for the exploration program, and also credits for Au and Ag help make the C1 look good

But i don't think that exploration costs, even if they are not capitalised, appear in the C1 cost. C1 is the direct cash cost of production of concentrate, not the "total cash cost" of production.

C1 cost is only intended to provide a "standardised" measure for comparing costs among concentrate producers, indirect costs, interest and depreciation are not included for this reason.