Huh, okay. Was there an episode where the difference was explained? I can't remember.

I'm not so sure about that, actually! Pearl's urgency and panic in "An Indirect Kiss" makes me think that a cracked Gem is only repairable for a limited amount of time— think about how Amethyst got more and more jacked up the longer her Gem was cracked. Too long, and she might have been permanently corrupted, beyond…