They used $400 gold and $1.20/pd copperThey used those numbers to come up with a 21 year mine life and cost of production around 75 cents/pound on average and an ROE of over 15%. This means that this is a VERY VERY PROFITABLE venture BECAUSE last I looked copper was over $3/pound and gold was over $600/oz. At $600/oz I get a cost of production of copper of about 10 cents/pound and you can probably add 10 years to the mine life if we are anywhere near these prices 20 years from now. Watch for aggressive buying from Chile Exchange today as they will have a visceral appreciation of these numbers.