Actually, this question has been answered a number of times in various venues. Just because a small object has a hole in it does not make it a bead. Buttons, washers, nuts (for bolts), and the like all have holes but are not beads. If, however, they are incorporated into a necklace, sewn onto a garment, or otherwise strung or sewn, they are being used as beads, thought their function remains a button, washer, or nut. Regarding the ring worn as a pendant, it remains a ring but used as a pendant.