We’ve seen it many, many times: the ship gets into a firefight, takes a few hits, shakes around, and consoles explode (possibly taking an unfortunate ensign with them). Eventually the battle is resolved with our heroes largely intact if somewhat shaken up. If it was a particularly nasty battle, there will be signs of damage: scorches on the walls, deformed equipment, busted lights, and rocks scattered about.
All of that seems reasonable… except the rocks, which look pretty out of place in a spiffy 24th century starship. So why are they there?
My headcanon is that there is some kind of advanced metallic alloy that, when exposed to extreme heat like an exploding photon torpedo, melts and then cools really quickly to look like a rock.
That was what I always thought, or advanced ceramics or something of that ilk … though all the dust would be really bad to breathe in!