"The Grasberg Mine is the largest gold mine... processing capability of 240,000 metric tonnes per day. Twice the size of an optimized L.C. if it was only processing it's own ore."

IMO, the optimized L.C. (the point where the maximum NPV for Kry occurs) is qty 17-20kt/d = 340,000t/d...much bigger than Grasberg.
At this size, 22Moz @ 0.9gm/t will be mined in 6.13 yrs.
Kry's share of the mine cost would be $1080M, amortized over 5 yrs equating to $269M/yr.
For this mine built and producing in 2yrs,
Kry cash flow:
yr3-7... $700M
yr8...... $969M
yr9...... $128M
With 514M O/S, 8% discount rate, $1150/oz gold, $340/oz cost, Kry NPV/sh = $3.48 after 40% Ventax.
Do you think Kry and CRRC are negotiating "optimization" along these lines?
Regards