Onyx noir véritable taille coussin, dessus plat, double biseau, avec trou

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 on the market is grey chalcedony that has been chemically treated to achieve its characteristic deep, shiny black color. Black Onyx is the top-selling chalcedony in the jewelry market and has a rich history of use in Art Deco jewelry design.

These genuine cabochons feature a cushion flat top double bevel profile with a pre-drilled hole, making them well-suited for pendants, earrings, and other fabricated jewelry settings. The uniform opaque black color and consistent form make them a reliable choice for professional jewelers.

Features

• Genuine black onyx (dyed black chalcedony)
• Cushion flat top double bevel profile
• Pre-drilled hole for versatile setting applications
• Uniform opaque black color throughout
• Consistent, professional-grade cabochon form

Specifications

Available Options

Notes

All black chalcedony — including black onyx — is grey chalcedony that has undergone chemical dyeing treatment. Natural untreated black chalcedony does not exist in commercial supply. This treatment is standard and universally accepted in the gem trade. Disclose treatment to end customers as appropriate.