OK, now it's official, Equestria is an inexhaustible source of precious gems

 1-You can find them buried two feet off the ground

 2-Spike buy and eat them as if they were bags of cheetos

 3-Cadence can transmute water into gems
 
  I say we must nvade … I mean, bring some democracy and freedom, to the cruel monarchy of Equestria

Not exactly, pretty sure pipes are designed with holding that kind of pressure in mind.