I am going to harvest these beads from this bib or collarette necklace, which looks homemade, and belonged to my grandmother. I would love to know more about them! What I can tell you:
they are opaque, shiny white, and cold to touch (glass beads, maybe);
they are slightly baroque (bumpy, irregular surface and shapes), which is why I haven't cleaned them as the texture is more visible;
they feel just barely oily or greasy to touch, but don't leave residue;
they are heavy, and make a clacking sound like glass beads;
they date to mid-twentieth century or older;
they don't have any discernable odor.
I think they are probably just soiled glass beads (go figure). Any knowledge or thoughts on these beads would be much appreciated!