Black Onyx
Stone

Black Onyx

Colour
Black
Care profile
Moderate
About the stone

Black Onyx is a type of chalcedony — a quartz with microscopic crystals — prized for its deep, uniform black.

A little-known detail: most of the black onyx on the market is dyed chalcedony, soaked in a sugar solution and then treated to turn black.

It’s a time-honored technique accepted in jewelry, not a trick — pure natural onyx without bands is rare.

Used since antiquity for cameos, seals, and amulets; its name comes from Ancient Greek and means 'nail' or 'claw'.

It had a major moment in the Victorian era: after Prince Albert’s death in 1861, Queen Victoria remained in mourning for the rest of her life, and dark stones became fashionable for mourning jewelry.

Then, in the 1920s–30s, black onyx shone in Art Deco, offering the perfect, geometric contrast alongside diamonds and colored gemstones.

Its color is an intense black, sometimes with white or gray bands.

Most specimens are cut in major lapidary centers such as Idar-Oberstein.

Associated with protection, inner strength, and balance, onyx is said to help with focus and emotional stability.

With a hardness of almost 7, it’s fairly durable, but can develop fine fractures under strong blows — so keep it away from impacts and harsh chemicals.

It’s easy to clean with a soft cloth. Its smooth, glossy finish is beautifully showcased in 925 silver for a modern, elegant look.

Black Onyx care

How to care for it.

Care profile
Moderate
Attention level
Cleaning
  • Warm water with soap or a gentle professional jewelry solution.
  • Avoid ultrasonic cleaners if the stone is not clearly compatible (e.g., some amethysts or topazes may be affected).
  • Avoid steam cleaning unless specifically safe for that stone.
Exposure precautions
  • Remove jewelry before intense physical activities or entering chlorinated pools.
  • Avoid contact with strong chemicals (chlorine, ammonia).
  • Some stones may lose color with prolonged sun exposure; store them properly.
Storage
  • Store in soft pouches or separate compartments to prevent scratches.
  • If the metal oxidizes easily (like some silver alloys), consider anti-tarnish strips.
  • Avoid areas with high humidity (bathrooms, saunas).

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