Onyx Stone: History, Meanings, Properties & More

Onyx informationThe onyx stone is a variety of chalcedony recognized for its gorgeous black or brown coloring and striped bands. But not all onyx stones are black. In fact, they come in vibrant colors weaved with magnificent bands.

Black is the most popular onyx color, and the color of power, mystery, and depth. Its neutral tone means it matches with everything. It’s a powerful companion for any color and any person. The onyx stone, known for its deep ebony color, shares all these qualities. 

You may recognize the name onyx from a few pop culture references. 

For instance, the Pokemon franchise includes two snake-like creatures named Onyx and Crystal Onix. In New York City, the historic Onyx Club was a swanky jazz club. During its prime, it held performances by greats like Billie Holiday and Dizzy Gillespie.

But what about as a gemstone? Onyx has a long and rich history filled with magic, royalty, and mythology.

Today, we’ll be getting into all the beauty, science, and history behind the onyx stone. Let’s begin!

onyx stone

What is an Onyx Stone?

Onyx is a dark silicate mineral recognized for its lined color banding and various spiritual properties.

If you’re a Leo, onyx is the zodiac stone for you! While Leos are known for their confidence and tenacity, these positive traits can be overshadowed at times by self-doubt or impulsive decision-making. Onyx can help by providing steady self-assurance and wisdom to see problems with clarity.

How about a summer theme? If you were born in August, a variety of onyx called sardonyx is one of your birthstones. Sardonyx was the first birthstone for this month, way back in ancient times. Why not pay homage to the past with a truly unique sardonyx pendant or ring?

Summer babies don’t get to have all the fun, though! Onyx is the modern birthstone for February, too. If the bright purple of the traditional birthstone, amethyst, isn’t your style, you’ll love the onyx stone’s sophisticated vibes. Plus, you can wear it with everything!

If none of these birthdays apply to you, don’t worry! Onyx is the traditional gemstone for the 7th wedding anniversary. If you or a loved one are celebrating, why not gift a stunning pair of onyx stones to commemorate the occasion?

Now, let’s dive a little deeper into onyx’s scientific characteristics.

Onyx Stone Specifications and Characteristics

As we mentioned, onyx is a silica mineral belonging to the quartz family. Within this family are two categories: macrocrystalline quartz, which are typical quartz stones like amethyst and citrine, and microcrystalline quartz. Onyx belongs to the latter, along with other gems like carnelian, jasper, and bloodstone.

Microcrystalline stones fall under the umbrella of chalcedony or chalcedonic quartz, too. Onyx is technically a subtype of a subtype of chalcedony. (Stay with us here, we’ll explain!)

When chalcedony has curved color banding, it’s called agate. When agate’s bands are flat and have white, black, or dark brown shades, that’s onyx. While some experts claim this, other experts like the International Gem Society (IGS) classify agate and onyx as separate stones.

Regardless of which stance you take, the chemical specifications for agate and onyx are quite similar.

  • Chemical compound: silicon dioxide

  • Mohs scale: 6.5 to 7

  • Color: black (primarily), brown, red, white, grayish blue, green

  • Crystal structure: trigonal (sub-system of hexagonal)

  • Luster: waxy to silky; Vitreous (glass-like) when polished

  • Transparency: translucent to opaque

  • Refractive index: 1.54-1.66

  • Density: 2.65-2.91

  • Cleavage: none

Clearly, there are a lot of details behind onyx as a mineral. But what about its gemstone properties?

Rough uncut onyx stone

Onyx Stone Properties

As a gemstone buyer, there are four crucial factors for knowing a stone’s true value: cut, color, clarity, and carat weight.

We’ll go over onyx’s value based on these 4 C’s of gemstone quality.


Opaque gemstones become cabochons or beads more often than faceted pieces. 

Of course, onyx is not like other opaque stones! While cabochons and beads are popular cuts, onyx’s shimmering surface and durability lend themselves well to many faceted cuts.

Pretty much any standard gemstone cut can work for onyx: round, pear, square, you name it!

The type of cut onyx is most associated with, however, is carving. In both ancient and modern times, onyx stones were fashioned into beautiful and intricate cameos and intaglios.

Cameos and intaglios are two types of stone engravings that usually depict people, either real-life dignitaries or mythological characters. Cameo carvings are raised against the background, while intaglios are carved into the background. Onyx cameos and intaglios date back to ancient Greece.

Other onyx carvings such as small figurines or sculptures are popular as well.

With any colored stone, though, the key-value factor is, well, their color!


While solid black onyx is undoubtedly what most people first think of, other onyx color varieties exist. These are actually much more abundant than the natural solid black form. Many of the pure black onyxes you’ll see on the market are actually dyed.  

You can usually identify onyx varieties like sardonyx, carnelian onyx, and Niccolo onyx by their coloring:

  • Sardonyx: Light or dark brown base, sometimes reddish or yellowish-brown

  • Carnelian Onyx: Deep crimson red to a red-orange base

  • Niccolo Onyx: Black base with thin, nearly translucent bands that appear light blue or light gray

The most common naturally occurring form of onyx, consisting of a black layer with white on top, is called “Arabic onyx.” Some gemologists call this variety “true” onyx. 

Most onyx's have multiple vibrant colors, like these blue onyx stones.

Blue onyx pair


Onyx stones usually don’t have any inclusions, giving them high clarity. However, clarity grades are typically only given to transparent stones. Since onyx is translucent to opaque, it doesn’t have a clarity grade. 

Even so, onyx could still be considered “eye-clean.” After all, “eye-clean” just means that you can’t see a stone’s inclusions without a magnification tool.

Carat Weight

You can find onyx in a variety of sizes and weights. Large masses are common and will have higher carat weights.

Carat weight is usually determined by a stone’s cut, however. For onyx, round cuts for faceting – typically 7-9 millimeters – weigh between 1-2 carats. Cabochons, on the other hand, can be anywhere from 0.15 carats to over 20 carats. 

Onyx’s weight can help distinguish it from other stones as well. For example, onyx sometimes gets mistaken for black obsidian, as they look almost identical. However, onyx usually weighs more than obsidian. Onyx can show color banding that obsidian doesn’t, too.

Since we’re on the topic of onyx colors, let’s look at some processes that enhance them.


As you know, onyx stones come in a variety of color combinations. Because of the stone’s signature color banding, a solid black onyx is incredibly rare in nature. 

Most of the pure black onyxes on the market today are dyed to achieve their deep, consistent color. Dyeing treatments can create other colors, too, such as dyeing clear chalcedony to create green onyx.

Heat treatments are common for onyx as well. When heated, onyx will lose its color bands and become one solid color. Dyeing and heat treatments can be combined, too. In fact, one ancient treatment process utilizes both.

The ancient Roman author and philosopher Pliny the Elder wrote about a method for changing or enhancing the color of onyx. According to Pliny, you simply boiled the stone in an acidic type of honey. 

Speaking of ancient times, let’s look at other instances of onyx throughout history.

Black onyx carving

Onyx History and Legends

Onyx gained its name in 77 AD by Pliny the Elder. This stone’s history is colorful, with various positive and negative onyx symbolism showing up over time. 

In China, people would actually avoid coming into contact with the stone for fear of it bringing bad luck. Medieval writers claimed that onyx could make you vulnerable to nightmares, arguments, and even demons.

During the Victorian era, people associated onyx with grief. After Queen Victoria I’s husband died in 1861, her mourning attire included statement pieces with onyx and other dark stones. Even the Arabic term for black onyx, el jaza, simply translates to “sadness.” 

On the brighter side, this negative association wasn’t present everywhere. Some societies even changed their views of onyx over time. 

For instance, Chinese Feng Shui utilizes onyx stones to provide protection and increase resilience. Ancient Indians, too, believed in the stone’s protective powers, as well as its symbolism for romantic partnership.

Some of the most famous onyx pieces date back thousands of years. The famous breastplate of the Jewish High Priest in 14th century B.C. included onyx as one of its twelve gemstones. The Great Cameo of France, sculpted in 23 AD out of sardonyx, is known for being the largest surviving cameo from ancient times.

Onyx Mythology

Apart from historical uses, onyx has a fascinating place in Greek mythology.

According to legend, this stone formed from a goddess’s fingernail. It may sound odd, but the story goes that Aphrodite, the goddess of beauty, was sleeping near a river. While she napped, her son Eros, or Cupid in Roman, used one of his arrows to cut off her fingernail. The nail then fell into the Indus river beside her.

Unlike mortals, however, the bodies of gods and goddesses couldn’t die, even if they’re separated. Instead, the removed fingernail transformed into onyx. Other versions of this tale claim the Fates, three beings in charge of destinies, turned the nail to onyx.

All of these stories and beliefs about onyx contribute to its spirituality. So, what is the spiritual meaning of onyx?

Onyx Stone Meaning

Onyx’s name is Latin for “fingernail” or “claw.” A similar Greek word, onux, is derived from the Latin term and carries the mythological legend discussed above. The name comes from its appearance as well. Many onyx stones had a cream-colored portion that “resembles the white of the human-finger nail,” according to the ancient sage Sudines.

A spiritual connection between onyx color and meanings exists as well. Some say that onyx’s color gets darker as it absorbs more and more negative energies. In general, black gemstones are associated with grounding and balance.

Onyx is known as the “Stone for the Mind” because of the mental aspect of its spiritual properties. Onyx symbolizes mental strength, mindfulness, and self-control.

Knowing a stone’s meaning is good, but applying it is even better. Based on all its symbolism and spiritual meanings, what is onyx stone good for?

Tumbled onyx healing crystals

Onyx Healing Properties

Using gemstones for healing has become increasingly popular over the last few decades. Healing stones allow us to break from the hectic noise of everyday life and practice a spiritual form of self-care. Onyx has healing properties of its own.

Historically, onyx’s physical healing properties included making wounds heal quicker and easing childbirth. Onyx can help hair, skin, and nails grow stronger as well.

Onyx’s positive effects as a “Stone for the Mind” include better memory, lower stress levels, and greater control over emotional impulses. This gem is beneficial for students, as it can aid concentration and help you tackle assignments one by one.

Speaking of emotions, many believe that onyx stone benefits those struggling with sadness. Whether it’s grief, detachment, or loneliness, onyx may help. This stone can help bring in those positive feelings of security, comfort, and connection.

You might prefer healing through the chakra system. What chakra is onyx? 

Black onyx activates and balances the root chakra, aka the base chakra. The root chakra is at the base of your spine and represents your foundation system – where you place your roots or come back to when you forget your way. 

When the root chakra is blocked, you may feel lost, hopeless, or anxious. Onyx can help open this chakra again, bringing back a sense of purpose and illuminating the right path forward.

Speaking of paths, let’s look at the more literal paths that onyx takes from its formation to the market.

Onyx Stone Origins and Sources

Onyx mines are located all over the world, with one or more on nearly every continent.

The most abundant areas for onyx are in the following countries:

  • Brazil

  • India

  • U.S. (Utah, Oregon, Rhode Island, California)

  • Australia

  • Madagascar

  • Uruguay

  • Russia

So, what happens inside these mines to create such beautiful crystals?

Heart shaped onyx carving

Onyx Formation

As we mentioned early on, onyx is a form of microcrystalline quartz. Unlike the coarse crystal grains of macrocrystalline quartz, microcrystalline quartz stones are fine-grained. 

These stones, onyx included, typically form inside the veins or open spaces in rocks when specific solutions cool or evaporate. 

Onyx can crystallize inside lava as well. Lava or volcanic rock have cavities formed by gas building up. When silica and other minerals get deposited into these spaces, they cool and become onyx. 

The next stop on onyx’s journey falls into the buyer’s hands. But how much does an onyx stone cost?

Onyx Stone Price and Value

In general, onyx is an affordable stone. But is onyx stone valuable? Well, its value, and therefore price, increases based on its treatments, size, and cut.

Since so many onyx gems on the market receive treatment, the price difference between untreated and treated onyx isn’t massive. Untreated stones will almost always have a slightly higher value than treated stones, however.

Faceted cuts like rounds, ovals, or marquise cuts are more expensive than onyx cabochons or beads. That’s because faceted cuts take more time and skill level to achieve. The same applies to carvings, as their price will take into account the level of craftsmanship applied.

For faceted onyx cuts, the price per carat can range from $1-7 on the lower end. On the higher end, onyx prices are $6-11 per carat. Cabochons come at much lower prices, ranging between $0.80-5 per carat.

Whichever onyx stone you choose, you’ll want it to last, right? To make sure it does, you’ll need to know how to take care of it.

Onyx cabochon gemstone

Onyx Care and Maintenance

Because of its high ranking on the Mohs scale, onyx is so durable that cleaning it is a breeze!

Grab a soft brush (like a toothbrush, for instance) and some warm water. With these in hand, you can quickly scrub off any debris from the surface. Dry with a microfiber cloth, and voila! Good as new.

Of course, some damage can’t be scrubbed away. Your stone can stay safe if you make sure it avoids contact with:

  • Harsh household chemicals (like ammonia)

  • Ultrasonic cleaners

  • Harder gemstones (any in the beryl, corundum, chrysoberyl, topaz, or spinel gemstone families)

While you can use mild soap on some onyx crystals, we don’t recommend it! 

Since most sold stones have undergone some sort of treatment process, they can be more porous than their untreated counterparts. Absorbing soap could dull their color or luster. Just stick to water, and you’ll be fine!

Ready to Show Off Your Magic?

You did it! Now you know everything necessary about the bewitching onyx stone. From its captivating color to its powerful properties, you can see why onyx is the most famous black gemstone on the market.

Onyx’s depth is clear from the start, but it brings a new depth to the lives of anyone who uses it, too. By granting wisdom and protection, onyx can help you find new opportunities. And when these new opportunities arrive, you’ll know which are the right ones to choose.

Where can I find onyx stone? Explore our selection of loose onyx stones here!

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