basically - they do an assay of ore going into the plant, and then "payablity" % of that amount - with reference to a "LME price" - typically (historically) it was 65% of the containined Ni, plus credits for Co / Cu, minus any deleterious elements (arsnic) ........and the price received was (typically) lagged 2-3 months "behind" the LME price .......
hope that is useful
rgds
V_H
MCR Price at posting:
37.5¢ Sentiment: Buy Disclosure: Held