Oval Black Onyx Cabochon

Black Onyx, also known as black agate, is dyed black chalcedony. Chalcedony is composed of microscopic quartz crystals not visible to the naked eye. Natural black chalcedony is exceptionally rare — virtually all black chalcedony available commercially is grey chalcedony that has been chemically treated to achieve its rich, uniform black appearance. Black Onyx is the top-selling chalcedony in the market and has a long history in fine jewelry, most notably as a staple of Art Deco design. These oval cabochons are available in a wide range of sizes, making them well-suited for rings, pendants, brooches, and other metalwork settings.

Features

• Dyed black chalcedony — the same material historically sold as Black Onyx
• Uniform opaque black color throughout
• Oval cabochon cut — smooth domed top, flat back
• Available in 12 sizes from 6x4mm to 25x18mm
• Suitable for a wide range of setting styles and jewelry applications
• A classic choice for Art Deco-inspired and contemporary metalwork designs

Specifications

Available Options

Notes

Black Onyx is universally treated material — the dyed process is the industry standard for this stone and does not diminish its commercial value or desirability. Natural untreated black chalcedony is extremely rare and not typically available in the gem trade. When disclosing stone treatments to customers, note that this material is dyed.