OK, there are beads that are beads by themselves, the "real" beads, no matter where we see or find them.
Then there are other things (naturally pierced stones, bolts, and so on) that become beads IF/WHEN used as such.
So, it is the intention of a human what turns an object into a bead, be it the manufacturer (i.e. peerless Art) or the user (i.e. a girl finds a naturally holed shell on the sand, strungs it on a thread and secures the necklace around her neck).
I hope I have it right now.