It's a joke referring to the debris that would come out of the consoles during battles and explosions.Explosive rocks?
Correct me if I'm wrong, but they didn't.
The plasma is what's running through the ships' EPS grid as far as I know. Its highly energetic, and there's bleedthrough/feedback that occurs when weapons hit shields and/or the hull (it might also be what's interfering with the plasma during weapons fire).
If you're referring to dilithium, that thing is down in engineering as far as I know... not in consoles.