Black Onyx smooth round beads are an opaque chalcedony quartz and has a fine texture and jet black coloring. These beads are smooth round beads with a polished silky luster.
4mm beads - the hole size is 0.8mm - big enough for a 24 AWG wire but may or may not fit a 20 AWG wire.
6mm beads - the hole size is 0.9mm - big enough for a 20 AWG wire but too small for an 18 AWG wire.
These beads may not be perfectly round and can range in diameter +/-0.5mm.
Strands are sold as temporarily strung. Strands are approximately 16" and can vary +/- 0.5".