$?Bill in a ? Life mine, page-2405

Yep, ok. I thought of that, but just increasing the overall reserve total (while increasing, at face, the asset value if the company) doesn't appreciably improve the project economics on a discounted cashflow approach, because, then you're then starting to discount cashflows out beyond 20yrs. So their contributions to the npv become relatively small.

Basically, it's to do with my Cu price & cost, and also my Au grade assumptions in the model, as well as the mining rate. Basically, on a discounted cashflow approach, the more you mine and process earlier on in the project life, the higher the npv. The reason I use only 25Mt ore/yr production rate is because it is very close to Productora's avg. 20Mt rate. I actually wanted to double it to 50Mt ore/yr production rate in my model, but was concerned about the capital investment cost. See if you look at the PFS, Productora required $US725M to build a plant and miming capacity capable of only about 20Mt ore/yr rate.

Anyway, hopefully someone here has done an npv on this and can help me. Cheers.