A Quick Guide on Buying Onyx Jewelry: An Expert Guide

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Known as the traditional black gemstone, onyx has been used in jewelry and as a protective stone since ancient times. Onyx used to be extremely valuable but today it is an affordable gemstone, and suits any budget.

Onyx is more than just a black rock. It comes in a variety of banded colors and can be carved into beautiful jewelry designs. With its smooth glossy luster, onyx jewelry is sleek and stylish and can be a part of any jewelry collection. And with black jewelry increasing in popularity, onyx is having a moment!

If you’re thinking about buying your own piece of onyx, here’s everything you need to know.

What is Onyx?

Onyx is a variety of layered chalcedony, similar to agate. In fact, the difference between onyx and agate lie only in the formation of their bands. While agate comes in curved bands, the layers of onyx are parallel.

Antique Cameo Pin isolated on a white background
A beautiful cameo depicting a female portrait engraved into sard onyx

Most people think onyx is only found in solid black, but in fact it comes in a variety of colors. The most popular, however, is solid black followed by the banded black and white. One popular usage for onyx was in the cutting of cameos and intaglios. Because of its beautiful layers, gem engravers could manipulate the colors to create beautiful reliefs.

Onyx is commonly found in many regions of the world, including parts of South America, India, Indonesia, China and Australia.

Buying Onyx

When buying onyx, whether it is online or at a physical shop, it’s important to evaluate its value by considering the following factors:

Onyx Color

As mentioned above, onyx typically occurs in banded alternating colors. Black onyx is the most famous variety of onyx and also the most common black gemstone but it is almost always dyed to obtain this color.

vintage onyx ring with diamonds
Vintage onyx ring. See more onyx rings here.

Apart from black and white, some other popular banded onyx varieties are sard onyx which has a brown base layer and a lighter upper layer and cornelian onyx which has a red base layer.

Evaluating Clarity of Onyx

Onyx gemstones generally have little to no impurities. They often have high levels of clarity.

They have a shiny to dull luster with most onyx gemstones being opaque. When buying onyx, look for a smooth surface, with no cracks or inclusions. This will ensure that the luster is uniform and smooth.

Deciding on the Cut of Onyx

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

Onyx stud earrings
Smooth cut onyx is equally intriguing as faceted onyx. See these faceted onyx earrings here.

Because this is a relatively soft gemstone, it also lends itself well for carvings. This is why onyx is popular in the making of cameo jewelry.

Onyx Jewelry

Onyx jewelry is sleek and stylish. A little onyx goes a long way, so unless you’re wearing a statement piece, opt for smaller sized onyx. Black gemstones are always eye-catching because they’re not a common choice, so onyx is an excellent way to stand out in a crowd with your jewelry.

A pair of delicate onyx earrings, or a small onyx pendant or ring is a perfect addition to every day wear. Because of its neutral color, black onyx will go with any outfit.

onyx studs for daily wear
Onyx studs are great for daily wear. See these here.

Some non-conventional couples who want something different are opting for black engagement rings. For them, an onyx ring makes a good choice as it is affordable and very beautiful. It is quite similar to the black diamond although not quite as durable shiny.

However, onyx is a softer gemstone and although it has excellent wearability, it still needs to be taken care of in order to prolong its life. We’ll discuss more on onyx care below.

Set onyx in yellow or rose gold for a vintage look and a strong contrast. When paired with white metals and accent diamonds, onyx has a modern, trendy look to it.

cuff links onyx
Black onyx makes for eye-catching male jewelry and accessories, like these cufflinks on Blue Nile.

Because of its masculine appearance, onyx is also a favorite for male jewelry. They are perfect in studs, rings and even in accessories such as cufflinks.

Onyx Engagement Rings

Black engagement rings aren’t everybody’s cup of tea, but for some non-conventional couples who want something different, they are the perfect option.

Onyx engagement rings are affordable, eye-catching and put simply, very beautiful. They’re a less expensive alternative to black diamonds.

However, if you’re looking for a sparkling, brilliant and traditional stone, then this isn’t it. And for most people, an engagement ring lasts a lifetime, so before you pick something very different, make sure you’re really comfortable with the choice.

Black onyx ring
Not as durable as a black diamond but equally beautiful, onyx is a choice for daring and out of the ordinary engagement rings. See this one here.

While onyx is similar to black diamonds in appearance, it doesn’t have the hardness that black diamonds do. It has a ranking of 6.5 to 7 on the Mohs scale, making it quite a soft gemstone. Although it has excellent wearability, it still needs to be taken care of in order to prolong its life.

While we don’t recommend onyx for engagement rings, if you’re willing to put in the work to prolong its life, then it’s a gemstone that can last a very long time. We’ll discuss more on onyx care below.

Onyx Treatments

Almost all black onyx on the market is dyed to enhance the color for even saturation. This is an industry-standard and is not unusual.

However, your vendor should let you know that such treatments have been performed on your onyx gemstone. Heat treatments are also commonly carried out on onyx.

The Value of Onyx

Onyx is an inexpensive gemstone and can be found to suit any budget. This makes it perfect for costume jewelry as well as large statement pieces.

Onyx diamond ring vintage
Onyx pairs well with expensive materials like the diamond and gold of this ring.

However, if buying a piece of onyx jewelry, you can attach value to the item by choosing a high-quality setting and design. This is especially important when choosing onyx bridal rings. Even though the gemstone itself may not be expensive and may even require replacing, the overall design will be of value.

Taking Care of Onyx      

Onyx is a relatively hard stone with a Mohs ranking of 7. 7 is an important number on the Mohs scale as it is the hardness rating of quartz, commonly found in dust. Any gemstone with a ranking below 7 can easily be scratched, even by dust. Onyx is quite a tough stone due to its composition, but can crack or chip if dealt a hard blow.

To clean onyx, use soap and warm water with a soft brush to wash the stone. Once washed, make sure the soap is rinsed off and the stone is dried thoroughly. It is not recommended that you use ultrasonic cleaners as these can damage the gemstone.

When storing onyx, wrap it in a cotton or velvet cloth, keeping it free from dust and from being scratched by other items.

Keep onyx away from chemicals such as harsh detergents, bleach and cosmetics. It is always better to take off any onyx jewelry when handling any sort of chemicals or engaging in outdoor/physical activities. Protect onyx from knocks and bumps, especially during strenuous activities. This applies especially to onyx rings which will likely be more exposed than earrings or pendants.

The Symbolism and Meanings of Onyx

Onyx is believed to be a stone for the mind. It is thought to help in improving memory, reduce stress and bring balance to the mind. It has been valued as a stone for neurological disorders. It keeps pessimism away and rids you of unhappy relationships.

Many people believe that black onyx heals grief and assists you to deal with separation and death. It eases your loneliness and sorrow, and enhances feelings of protection and love.

Historically, onyx was also believed to be able to heal skin diseases and wounds. It is known to be a protective stone, and has been used in protective amulets. When worn around the neck, onyx was also thought to reduce lust and give a person mastery over their emotions.

Onyx is an important stone in crystal healing and is believed to give strength, center energies and align you to a higher power.

*Disclaimer: Jewelry Shopping Guide does not guarantee or validate any of the claims related to the metaphysical and alternative healing powers of this or any other gemstone. This information should in no way be used as a substitute for medical advice.

Where to Buy Quality Onyx Jewelry Online

When purchasing onyx jewelry online, always ensure that you’re buying from a trustworthy source.

Always check the after sales policies, customer reviews and quality of the product. Purchase from a store that allows easy returns so you can buy without risk. Note that you can’t return customized jewelry to most stores, as that is an industry standard.

So where to buy onyx jewelry online? We recommend the following stores:

Etsy has a stunning range of onyx jewelry, ranging from a few dollars to several thousands, suiting every style and price point. Each Etsy boutique operates as its own store with its own policies, so check this prior to purchase.

Blue Nile has a very good onyx collection featuring high quality pieces at reasonable prices. Blue Nile is known for being the largest online diamond retailer and has a proven track record of many years. 

Dani Rhys

Dani Rhys has worked as a writer and editor for over 15 years in the jewelry niche. She holds a Masters degree in Linguistics and Education. She has always been interested in expression through fashion and accessories, and her extensive experience in the field has made her a respected voice in jewelry trends and education. As the chief editor of Jewelry Shopping Guide, she not only leads the content strategy but also shares her insights through engaging articles. Her passion for storytelling is reflected in every piece she curates, exploring the intricate relationship between jewelry and personal identity.

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