"WRN's shares are currently trading about 50% higher than they did two months ago. Western's Feasibility study for Casino showed excellent economics with a 20.1% after-tax IRR and a $1.8-billion NPV at an 8% discount rate (based on US$3 copper and US$1,400 gold)."

Gold is bigger there so we have to adjust for the current realities. That does make a bigger impact on their IRR. Gold

Digression:

Gold is expected to remain below $1400 through mid 2015. It's possible it will be surpressed even longer and a number of companies will face critical cost factors. Some people think as high as 40% of the smaller gold companies will shut down production. This will cause a revaluation of labour. I suspect that's the intended goal for the over all mining industry. Supply and demand metrics are not at play in the usual way. Demand is healthy yet the price is low so where is the money? Paper gold is skewing everything. As supply constricts will price rise? Only if people wake up to the lack of physical gold their paper is supposed to be backed by. "Currently, the public seems to be content buying imaginary gold!"

Base minerals are less effected like gold because we consume them. Run short of these and suddenly car prices rise and bridges become expensive. Gold is mostly worn or horded. Try wearing your paper gold around your neck!

When people willing believe in the imaginary things are apt to go horribly wrong for them. http://www.policymic.com/articles/85541/nasa-study-concludes-when-civilization-will-end-and-it-s-not-looking-good-for-us (So even NASA is finally coming around to the realities)

At some point physical gold will have to set itself apart from the paper gold or all gold mining will stop. The paper gold people believe real gold is no longer required because people are too stupid to notice that it's already not there. People who want the real stuff are having a hard time getting orders. They've been hollering about it for a while now and no one hears them. This is solid proof of the above.