What's the cheapest and simplest way to crush stone ? Does not have to be portable. Hammer mill, jaw crushed, old fashioned stamper or even older fashioned/ancient Arrastra
Dolly pot is the cheapest & simplest way.
It's the best way to work out if you've got gold bearing rock too before worrying about bigger systems.
If you already know you've got gold bearing material then these days I'd reckon something like these would be far more effective but may not be the cheapest option: http://www.armstrongindustries.com.au/grb-777-mini
I wouldn't say simplest but definitely cheapest! Dolly pot is much better. I smashed up a rock so I could fit it in my dolly pot on the weekend and shards flew everywhere. Lucky the rock was baron and no gold was lost.