A Bold Favorite

Tumbled Onyx Gemstone Cabochon Estate Jewelry

Onyx refers to the black varieties of chalcedony or agate. Agate is a rock that encompasses several minerals such as silica, chalcedony, and quartz. This composition creates a banded aesthetic perfect for carving cameos. Onyx agate is traditionally opaque black with white banding.

Chalcedony is more simplified as a species within the mineral family of quartz. Chalcedony is cryptocrystalline meaning it’s comprised of tiny interlocking crystals instead of growing as one large crystal like quartz’s amethyst or citrine.

Onyx chalcedony is traditionally translucent to opaque and uniformly black in color.

A uniquely colored variety is sard onyx which has a brown carnelian base that transitions to black with white banding and is considered to be an agate rock.

This stone is readily available globally which allows for it to be used frequently and creatively.

Estate Onyx Jewelry Philadelphia Carved Medusa Gemstone Earrings


Onyx’s name derives from Greek’s ‘onux’ to mean “fingernail. This coincides with Greek lore that Eros, the Greek god of carnal love, cut the fingernails of Aphrodite, the Greek goddess of emotional love, while she slept. Fearing the consequences of having cosmic power within the mortal realm, the gods decided to turn the clippings into an inert stone, birthing onyx as a gem.

As Jewelry

Since onyx is within the quartz family, it is a very durable gem. It is most often cut as a tablet or as a cabochon to display its intense black coloring.

Onyx agate cameos are popular with the white portrait contrasting a solid black background. The stone is a favorite for carving intaglio to be used in signet jewelry.

                                                           Shop our favorite onyx pieces here.

Philadelphia Estate Jewelry Quartz Intaglio Signet Rings


Onyx can be washed with warm soapy water and a soft bristled brush. When being stored, it should always be wrapped to ensure it will not be scratched by harder stones like diamond and sapphire. As always, avoid harsh chemicals when wearing any kind of jewelry.