From the 2013 FS.  I know it's outdated, but think most of it is still somewhat relevant.

Variations (estimated) per the 2013 sensitivity analysis:

• Exchange rate: 75M per point
• Copper: 50M per point
• Operational cost: 40M per point
• Capex: 30M per point
• Gold: 20M per point

Current parameters:

• Exchange rate: from 0.97 to 0.77, 21 points favorable
• Copper: from $3.25 US to $3.50 US (estimated), 8 points favorable
• Operational cost: from $13.25/t US to $8.66t US, 35 points favorable
• Capex: from $3.26B US to $2.65B US, 19 points favorable
• Gold: from $1445 US to $1400 US (estimated), no significant change

This brings me to a pre-tax NPV (8%) around 4.5B US. 

Assuming they lose about 15% of cash flows due to royalties, that brings my estimate down to $3.8B US for 100% of the project.

Moly price could affect the numbers unfavorably by a couple decimals if they use something around $10 US.

IMO.

MoneyK