It was a black onyx media. I can't recall the exact name right off. Wasn't black beauty. By trade I work with all types of concrete. I've been sandblasting for years with different sands to show more or less aggrigate. I've also used glass and various other types of media. I hadn't used this before, but it worked pretty well. It struggled a bit to take the powder coating off, but was a soft enough media not to damage the casings even having to let it eat at the powder coating.