But crystals are EVERYWHERE in equestria.. how hard is it to pick up a rock, grab out a crystal, get it cut to shape and put a chain through the top of it?
Also, even here in Equestria, crystals are far more abundant than gold
No, because when you dig for resources or to clear land and the whole dirt beneath you is 1 part crystal or gem shard for every 5-12 parts dirt you're gonna have a looooot of leftovers xD