Ornate Filigree Dangle Earrings with Black Onyx Stone The onyx are 8mm round stone beads. These dangles are added to silvertone earwires, and the wires are white gold plated. The total length from the top of the wire to the bottom of the earring is just under 3 inches. Also see the photo with a penny for size comparison. We'll also add rubber earring backs so you can keep them secure.