Ann: C4 Iron Ore Mine September Update, page-10

Yep. It's not exact rocket surgery, but;
( Tonnes Sold x Sell Price) - (tonnes Sold x C1 Cost) = EBIT
Tonnes Sold x Sell Price x 5% = State Royalty = EBIT-R
EBIT-R x 0.7% = Nett Profit After Tax
70% NPAT = GWR attributable profit.

I figured it as $60M - $31M, which washes out to about $15-16M attributable to GWR, and $3-4M to PRG. I haven't put much more effort into it, I'm sure there's a few hooks from PRG in there beyond the $1.7M repayment of capital, plus the mine gate costs and mining costs of the 160Kt of stuff sitting in Wiluna ($1.6M?) that has been paid for but not sold.

Still, they had a decent run of it at world record Fe prices, which everyone knew wouldn't last. But mid-term if Fe 63% doesn't top A$150/t it's lights out for another 5-8 years.