C1 cost is the Production, mining, shipping and royalty costs plus treatment charges(inc impurity penalties)less the silver credit. It does not include the cost of the payability factor.
But it is worked out on net production after the payability factor - so if gross production is 100mil lbs, then C1 cost is worked out on 83.5mil lbs.
So if your C1 costs total $US50mil($A71mil) then your C1 cost is US60c.
Attached are the figures for Jun20 quarter - if you have any doubts you should tick them off against the figures quoted in the quarterly report and then look at how I calculated each of the four lines that make up the C1 cost.
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