Don't forget to factor in a clearance rate for the auctions. I use 83.6% which is average clearance rate Gemfields achieved from 5 auctions June 2015 to June 2017.
Also, Mustang only own 65% of the current tenement. That means 35% royalty to Regius. I treat this as a cost. It's not confirmed whether the figure of 50% for costs we were given in discussion at the General Meeting includes that royalty.
You don't seem to have accounted for Mozambique corporate income tax of 32%????
