I agree, why would they pay $8m. But if it's worth $4m, and all...

I agree, why would they pay $8m. But if it's worth $4m, and all other bidders would be looking to pay $3.5-4.5m, then you could come over the top at $5m and not feel too bad about it, given you'd get half of the money back in pocket. $8m would be ridiculous.

I'm just using a typical PER, for a snapshot in time. Agreed the Weeks royalty is a finite resource but there's a fair bit of life in that basin yet I'd say - likely enough for DCF analysis to bring future years to basically zero NPV and the PER assumption to hold. Perhaps a 15x PER would be more appropriate though..:

https://www.marketindex.com.au/statistics

What if instead you looked at the ~$1m p.a. from Buru and ~$600k p.a. from Weeks underpinning a ~1.5cps annual dividend? There's your 30-35cps of value too (at a 4-5% yield).