Vintage Onyx Jewelry Buying Guide

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From the Greeks and Romans to the Victorian Era and Art Deco Era, the use of black onyx has been very prevalent in fine vintage jewelry! Learn all about vintage onyx jewelry, its history, meaning, and things to keep in mind when purchasing.

Vintage Onyx Jewelry - black onyx stone

What is Onyx?

Onyx is a variety of the mineral, chalcedony. It has parallel bands of white and many varieties of colors, such as red, brown or black. In Vintage jewelry, you’ll most often see onyx just as a solid piece of black, instead of with a banded white or other color varieties. 

  • Hardness - 6.5 - 7
  • Durability - very good

Because onyx is a relatively hard stone, it stand up well to daily wear. It is a suitable stone for men and women's engagement and wedding rings. Black onyx is the classic birthstone of July.

History of Onyx in Jewelry

The word ‘onyx’ comes from the Greek word meaning claw, nail or fingernail. This name could come from either the similarities in color of the white band to a fingernail or a mythical legend about fingernail clippings of the gods turning into stone.

We start to see the use of onyx with the Egyptians in bowls and pottery. The Greeks and Romans often used the stone for intaglios or hardstone cameos. The carvings were one color, while the background was another.

The dark black color of onyx made it extremely popular during the Victorian Era. Here, we see Queen Victoria mourning the death of her husband Prince Albert. Queen Victoria mourned not just in outfits, but with jewelry as well. We see the use of black onyx as side stones, but also center stones to many of the jewelry pieces during this time.

The next era we see an extensive use of black onyx is that of the Art Deco Era. This era is known for dramatic contrasts in color and hard, geometric designs. The black onyx perfectly compliments and allows the shimmering diamonds to stand out! Often in this era, you will see side stone pieces of onyx cut into geometric shapes, such as baguettes, french cuts, and square or rectangular pieces.

Onyx is very popular as a cameo gemstone, as it lends well to carving. It is shaped into beads for necklaces, teardrop or geometric shapes for earrings, and bold cabochons for rings. 

Black Onyx Meaning

A stone of protection and balance, it is believed that black onyx has the ability to deflect negative energies and emotions. This stone is associated with bringing emotional balance to the wearer. 

Black onyx is said to help heal grief and assist you in dealing with separation and death. It can ease your loneliness and sorrow, and enhance feelings of protection and love.

Types of Black Onyx Stones

There are two types of onyx used in jewelry: natural black onyx and agate black onyx, which is dyed black.

  • Natural black onyx is naturally black with the occasional light colored band. 
  • Agate comes in a variety of colors and can be artificially dyed black (labeled as D agate or D black onyx).

The process of dying agate requires boiling the stone in a sugar solution, then letting it steep in sulphuric acid. When the acid hits the sugar, black carbon is created, which seeps into the stone. 

Both have the same durability and there is no price difference. People who prefer an all-black stone may opt for dyed agate, as many natural onyx stones will have bands of light color or white running through it. 

Dyed onyx was liberally used during the Art Deco design period, where deep contrasts and bold colors were in style. 

Vintage Onyx Jewelry- black onyx earrings

Black Onyx Cut, Clarity, Color and Carat


Onyx can be cut into any popular gemstone shape such as round, pear, emerald, square, or marquise.  It is often cut into smooth glossy cabochons or is faceted to maximize the luster. 


Onyx gemstone typically have little to no impurities and often have a high level of clarity. Most onyx gemstones are opaque with a shiny to dull luster. 


As stated above, onyx generally occurs in banded colors of black, white, browns and reds. Pure black onyx is the most popular variety of onyx and also the most common black gemstone but it is almost always dyed to obtain this color.

Some other popular banded onyx varieties are sard onyx (has a brown base layer and a lighter upper layer) and cornelian onyx ( has a red base layer).


Naturally occurring black onyx and dyed agate black onyx are very affordable gemstones due to their bountifulness. Price per carat averages around $9.00 or less, and the value of the stone does not increase much with larger carat sizes.

Black Onyx is popular in Men's Jewelry 

Best Metals for Black Onyx Jewelry

  • White gold is best avoided, as it needs occasional re-plating with rhodium to keep its white look and this can damage the stone. 
  • Black onyx looks best with sterling silver or platinum.
  • Onyx set in yellow or rose gold offers a lovely strong contrast.
vintage black onyx jewelry

Black Onyx Gemstone Pairings 

Black onyx is often paired with diamonds. When paired with white metals and accent diamonds, onyx has a modern, trendy look to it.

Things to Keep in Mind When Shopping for Vintage Onyx Jewelry

  • Onyx is a relatively hard stone, coming it at 6.5-7 on the Mohs hardness scale. You’ll want to make sure that none of the onyx is chipped or damaged.
  • Due to its porosity, onyx is often dyed. This dying doesn’t impact the stone negatively, as it is often hard to tell if it is dyed or not. The purpose of dying onyx is to help create a uniform look in color.
  • Clean your onyx jewelry with a moist cloth, not with any sort of chemicals. The porosity can be negative in that sense, and just water will be sufficient.
  • Black onyx rings are valued on a large part by how the gemstone is cut, carved, and set. Black onyx gemstones with custom cuts, detailed carvings, and custom settings will have a higher price tag than a commercial cut and set stone.

Where to buy Onyx Vintage Jewelry

As with most Vintage jewelry, onyx pieces can be found at vintage sales, shows and shops. Etsy can also be a great place to purchase jewelry.


Onyx is a beautiful addition to any piece of jewelry. Try looking for a Victorian or Art Deco piece to add to your collection!

Happy Shopping!

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