Seeing the photo in your reply post, I am reminded of some early (usually gray-to-black) faience beads from antiquity. These can be seen in Lankton's "A Bead Timeline," Chapter 3, specimens 368.

These faience beads date from ca. 5,000 years ago, and were found in Syria.

However, I cannot say I recognize your bead. Nor can I tell from surface characteristics whether it is made from glass, something glassy (faience), metal, or whatever.

JDA.