Hi Salt - if you want to liberate micron sizes then a hammer...

Hi Salt - if you want to liberate micron sizes then a hammer mill won't do it for you; you'd need to go to something like a roller mill if dry processing, or a ball mill if wet processing. In this case you can maybe avoid further milling by going straight to leach. I'd have to look back at the testwork report to see what grain size they used as I don't recall whether they used additional comminution or not.

But yes, grab the more easily recovered gold first - via an optimized gravity circuit - and move to CIL at an appropriate later time to improve the overall recovery.

Not sure that I follow you regarding the reported 80% recovery. If RR is reporting 80% recovery into the cons then that's it, the balance 20% would be in the tails.