If you're wrapping glass beads with silver wire, a steel-shot tumbler is probably safe. I've never had a problem with glass or enamel in a tumbler. More delicate stones, like lapis, amber, untreated turquoise, etc. might be damaged, however.
What about Swarovski crystals. Can they be used in a tumbler? I
don’t imagine the AB can as the coating is delicate and will probably
come off, but the plain crystals… I’ve yet to learn if they can be
placed in a tumbler with steel shot.
Michele