Himalayan salt

We break piece off with our small kitchen hammer and then use a marble mortar and pestle. Works pretty quickly.

I'd make sure it's been crushed up pretty good with a hammer before putting it in a Vitamix or Food processor.
I ruined a blade on a older model Vitamix trying to grind some Parmesan cheese rinds. Apparently, according the VHS tape it can turn wood into sawdust but not so much cheese.

I grind it on a microplane.

Chisel and hammer into smaller pieces. Then crush in blender or even better, Vitamix. Spare the meat grinder.