RE:Treatment charge of 150=aisc cost of .8Namehij, may I correct your calculations? You re calculating with AISC but outstanding credit can only be payed back with profit, so you have to calculate with total costs (see the correct calculations from @firecracker74) . Means you have to add around 0.10USD/lb to your costs. Further, dont confund variable TC with the yearly TC, if you look at long term charts over several years, variable TC are normally substantially lower then the fixed TC so even though you ll see 150 TC right now, calculating with 150 TC for the whole year 2021 is too optimistic. But your generally optimistic view is not wrong imo.