I probably don't need to add a lot to what CMO has said except...

I probably don't need to add a lot to what CMO has said except go back to the basic difference between Wingenella ore and WMP ore. The former is lateritic needing HPAL (high-pressure acid leach) and the latter sulphides which generate a concentrate that is smelted then refined by the Sheritt Gordon process. The two biggest differences are All HPAL ore need to be leached only say 1% of the ore being concentrate needs further treatment. The difference means in terms of return on capital the Wingelena ore is a secondary return sulphides are a primary one. that leads to what CMO has said in terms of capital spend.

The other wrinkle I would add to CMO's call on $20 K/lb is it will need to a sustained $20K/lb Ni is notorious from running up higher than that level and dropping back down. You don't want to be outlaying $2.5B (c.f. $1B for WMP) and finding it only stays that way for 3 years. (possibly the 3 yrs you took to build it!) I guess it depends on your outlook for Ni driven by batteries. However, I note IGO have a major mine in the area did a study ended last Dec, that effectively concluded they would not get enough of a return form (hydrometallurgically) secondary processing of their Ni Sulphide concentrate to Sulphate (or hydroxide) suitable for battery manufacture based on the price difference.

I think it was a decent question to ask and I have avoided the thermodynamics. ALL IMHO.