Black onyx is a form of agate, or chalecedony quartz, which naturally forms in concentric layers in a variety of colors. Onyx is created in crevices and cavities by the cooling of molten volcanic rock.
8mm has 2.5mm hole
10mm, 12mm and 14mm have 3.0mm hole
*These beads are without (w/o) crystals. NO crystals. For onyx with crystals, please see onyx fireballs.