Color:
Expected to be black, but most onyx today is dyed to achieve the color. Onyx can contain bands that range from white to reddish or dark brown to black.
Gem family:
Chalcedony
Birthstone:
December
History:
Formed in the gas cavities of lava, onyx was used by the ancient Greeks, Romans and Egyptians.
Use in jewelry:
Ideal for carving intricate designs and most commonly used for rings, beads, pendants, bracelets and earrings.
Mohs hardness:
6.5-7 (1 softest to 10 hardest)
Treatments:
Heated and dyed to increase depth of color.
Care:
Wipe with a soft dry or slightly damp cloth.
