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How much is Opal worth: value, price and key factors

Besides being gorgeous, one of the best things about opal stones is their color variety.

Natural opal gemstones can come in many different colors, from white to red to green and even black.

Synthetics try to mimic their beauty, and some do so extremely well. But when it comes down to it, people are willing to pay a pretty penny to get their hands on some opal.

natural boulder opal gemstone

Opal can fetch such high prices that some stones are even more expensive than diamonds per carat!

Rare black crystal opals can sell for thousands in their natural state, and can even be found in museums across the world!

In this post, we’ll discuss just how much opal is worth, explore how natural opal is graded and explain the value of opals:

The world’s rarest opal: the Virgin Rainbow

According to Forbes, the rarest opal in the world is the Virgin Rainbow. This opal is also one of the most expensive opals in the world with a price tag of over 1 million dollars!

It formed as a fossil over hundreds of years and is considered one of Australia’s national treasures.

This opal is special, not only because of how it formed, but also because of its unique fluorescent properties.

It glows in the dark, and the darker it is, the more beautiful it fluoresces.

The Virgin Rainbow was found in one of Australia’s most productive mines in Coober Pedy, and today, its home is the South Australian Museum in Adelaide.

Types of opals

Opals can be either natural, synthetic (lab-created) or imitated, but in this post, we’ll be focusing on solid, natural opal gemstone.

This is still a huge factor when determining how much opal is worth, because natural is more expensive.

Most of the world’s supply of opal is found in Australia, but there are also productive mines in North and South American countries like the United States, Honduras and Brazil.

Opals occur naturally in sedimentary rock and fossil, and are formed in cool, wet environments close to the earth’s surface.

This is why opal is relatively easy to mine, and historically picks and shovels were all that were needed.

Opals can be split into many different categories, but generally, how much an opal is worth is first dependent on how it was formed.

Solid gemstones

Solid opal is the most valuable or precious, especially those domed into a cabochon (cut into dome shape at the top and flat at the bottom).

These occur in different colors, but those with a strong play of red, and lusters of orange, green and blue hues have big price tags.

Black opals are also very rare, and some from the notorious Lightning Ridge area of Australia have sold for $10,000 per carat.

Other popular opal body colors include green, brown, yellow, purple and gray.

Opal triplets

Opal triplets are more common than doublets. They are 0.5mm thick slivers of opal attached to a flat backing and glass-like dome top.

Typically, the backing is made of black potch (a type of opal), but it can also be made of industrial glass and plastic.

The top may be made of glass, but the best quality dome top is made of clear quartz.

All three layers are then held together by epoxy resin, which should last a long time.

These layers make the opal more durable and they help to enhance its natural appearance.

Triplets are typically used to make opal jewelry and are what most people own.

Opal doublets

Opal doublets are a thick cut of opal, usually about 2mm thick with a black backing.

These opals are less expensive than solid gemstones, but they still hold good value.

High-quality opal doublets are harder to spot than opal triplets, but you can usually distinguish them by looking at them from a side angle.

It will show a continuous line around the perimeter where the backing is attached.

Doublets are less durable than triplets and are closer to solid gemstones because they lack the protective covering on top.

Matrix opals

Gemstones are typically formed within rock and are separated during mining.

Sometimes, however, the host rock penetrates the gem or mixes with it during formation.

This is called a matrix. In other words, it’s ‘opal in host rock’, or opal that is mixed with its host rock.

(Note this is not the same as boulder opal, but it can exist as a combined version called boulder matrix opal)

This type of opal is sometimes referred to as “Type 3 opal“. It is slightly stronger or harder than pure opal, but is less valuable.

Synthetic vs fake opals

Synthetic opals are not considered fake, even though they did not come from the earth and are created in labs.

This is because they have the same chemical and physical properties, while imitation/fake opals only share a similar appearance.

Synthetic opals are less valuable than solid gemstones, triplets and doublets.

Fake/imitation opal is the cheapest and generally reveals its inauthenticity from its low price point.

Grading natural opal

Opal stone is graded using several characteristics. These include:


Type can be split into:

  • Homogenous (meaning it’s composed of precious and/or common opal)
  • Boulder (where it carries a piece of its host rock)
  • Matrix (where the fractures and pores of the host rock are filled with precious opal)

Body tone

Body tone refers to the color of the background of the opal. This can be black, white or dark (shades of gray).

Body tone determines how well it displays colors. Black body tones tend to be better at this, and are graded from N1 to N4.

N5 to N7 are used for lighter body tones.


Transparency of natural opals ranges from opaque to translucent, and their value is based on the type of opal.

With black opals, the more opaque the background is, the more it is valued.

However, with crystal opals, greater transparency is favored. It’s all about how well it displays this next characteristic, play-of-color.


This is a phenomenon within natural opal that causes light waves to refract or bend when they encounter silica.

As it bends, it reflects the colors of the rainbow or spectral colors.

The greater the play-of-color, the greater the value of the opal. Additionally, rarer colors such as red and blue fetch a higher price.

Therefore, crystals of the same cut, carat, brilliance, etc will vary in price, and opal with blue colors will be worth more than say a blue and green opal.

Similarly, a red opal will be more valuable than an opal that has blue, green, yellow and orange.

The play-of-color ratio to the background or body color is also an important factor.


The brighter the color is, the more an opal is valued. This is called its ‘brightness’.

A small opal with a bright color that is still visible in dim light is worth more than a larger opal with a weak color that only shows in sunlight.

Brightness may be described using words like ‘brilliant’, ‘bright’, ‘subdued’ or ‘dull’.


Opals display many different patterns. They are so unique that it is impossible to find two opals with the exact same pattern.

The best patterns include:

  • Harlequin– These have large sections of color, many of which are the same shape or size. True, or distinct, harlequin patterns are extremely rare and very valuable. 
  • Flagstone– These have large sections of color with straight edges
  • Chinese writing– These closely resemble Chinese characters and occur in thin strips with overlapping colors.
  • Ribbon– This pattern has narrow, parallel lines which lay side by side 
  • Straw– This is similar to ribbon, except the colors overlap like pieces of flattened straw
  • Picture stones– These resemble paintings or drawings of people, objects, animals, landscapes, etc.
  • Flame– This pattern is usually a red or orange flame that is spread around the opal

Other patterns include rolling flash and broad flash. The former has large sections of color which roll as the stone is turned, while the other has a similar appearance with the colors flashing as it is turned or tilted.

Pinfire patterns have tiny specks or dots of color, while floral patterns are larger and random.

Palette patterns resemble the color palette of an artist.

At the lowest end of the spectrum are indistinct patterns. The pattern is so poor that you’re not able to tell what it is easily, and it can look like a bunch of colors muddied together.


Irregular, asymmetrical shapes are worth less than opals with regular and symmetrical shapes.

Thickness, polish and calibration are also important considerations.

Cutters will always try to save as much of the natural opal as possible, so you’re more likely to find opals in irregular shapes.


Cracks, pits, matrix and crazing all influence how much the opal is worth.

Decreased clarity can mean a lower value.

Clarity will also factor in the presence of inclusions, like plant matter, matrix and fossilized insects like Beverly, the Bug.

Synthetic and lab-made opals don’t have inclusions. This is one way to tell if an opal is natural or not.

Carat Weight

One great thing about opals is their low density, and therefore, how comfortable large opals can be to wear.

With that being said, large opals are usually on the more expensive end of the spectrum.

While shopping for opal, you may realize that some smaller opals cost more than larger opals.

Carat weight does not make or break opal pricing. Other characteristics like pattern and play-of-color are considered more important.


Since opals are naturally fragile, backings are sometimes added to make them more durable.

These are still valuable and are preferred by some. They are the same thing as doublets and triplets.

Solid gemstones may be referred to as ‘rough opal’.


Origin is very important when discussing opals. Australian opal is the most valuable, followed (not very closely) by Mexican, Ethiopian, Brazilian and Peruvian opals.

The least valuable opal on the market is typically mined in the United States in Oregon and Louisiana.

How to assess the value of an opal

Gemologists are of course much better at evaluating gemstones like opals, but it doesn’t mean you can’t do your own evaluations at home.

Using this simple guide, you can analyze your own opals and even do a good job at telling how much opal is worth:

Start with its body color and transparency

The first thing you’ll want to make note of is its body color. Black or dark crystals are typically more valuable.

Transparent crystals with color patches are next in line, followed by opaque, or milky opals, which are considered common and have low value.

Then, access the play-of-color and pattern

Pay close attention to the ratio of the play-of-color to the body color. Is it intense, or is it subtle?

How many different colors can be observed? When it comes to opals, more is always better.

Vibrant, red colors are most prized, followed by orange and yellow, all the way down to cool colors like blue and green.

Note this is not a hard and fast rule. Even though red is typically more expensive, if it’s a dull color, an opal with a bright blue may be more valuable.

Similarly, if the pattern is considered rare, and is distinct, an opal with blues and greens can be more valuable than muddy reds and oranges.

Check the clarity and look for assembly

Start by looking for crazing or pits. These are the same as cracks or fractures.

You’ll need a magnifier. These decrease the value of the opal (remember they’re already relatively weak).

If there’s a matrix, the value decreases immediately.

Observe the opal from the side to see if it’s a solid gemstone or an assembled opal (doublet or triplet).

Solid gemstones are more valuable.

Lastly, shape/cut, size and origin

The last thing you’re going to pay attention to is its shape/cut, size and origin.

The best course of action is always to preserve as much opal as possible, so there are a lot of irregularly shaped opals out there.

The most prized is the cabochon, followed by other symmetrical shapes like round or square

You may think a big opal is the most valuable, but if it’s small and has great play-of-color and brilliance, it’s going to beat a huge opal every time.

Lastly, check on the origin of the opal. The most expensive opals come from Australia, but a fire opal from Mexico or ‘Mexican fire opal’ can be more valuable.

The least valuable opals tend to come from Ethiopia and the United States.

How much is opal worth by color/type?

There’s a committee in Lightning Ridge, Australia, that meets every Saturday to value opals.

However, this is not the same for all opals sold in the world. To date, there’s no standardized price per carat for opals (and most other gemstones).

In the real world, a miner will have one price, but if you bring it to a gemologist or opal valuer, you’ll get another price.

Plus, the seller has to make a profit, so that same opal can have an entirely different selling price from the first two.

What we can do is work with averages and ranges, and give the best estimate for how much opal stones are worth.

This is how much opal is worth for 10 carats of each type of opal:

Common opal

Common opals are the least valuable type of opal in circulation, and are sometimes advertised as ‘green opal’ and ‘pink opal’.

These include translucent to opaque opals with no play-of-color or are just one solid color.

These sell for as little as $7 per carat sometimes but can go up to as much as $300 per carat.

Don’t be surprised if you see common opal being sold per gram instead of per carat.

A $50 bill can get you a 10-carat opal with change left over!

White opal

White opals are a step above common opal. These range from translucent to transparent, and are sometimes called ‘milk opals’, ‘water opals’ or ‘crystal opals’.

They are among the more expensive opals and can range from $10 up to $6000 per carat.

A 10-carat white opal can cost as much as $70,000!

Blue opal

Blue opals typically come from Peru, and are also called ‘Andean opals’. These are different from common blue opals and resemble the colors of the Caribbean Sea.

10 carats will run you about $700, which is relatively affordable in comparison with other types.

The typical price range per carat is about $7 to $300.

Black opal

Black opal crystals are notoriously expensive, and if you manage to get your hands on one, you’re lucky!

The price range per carat starts at $60, but they can fetch mind-blowing prices of $10,000 per carat because of their brilliance and excellent play- of- color.

If you’re planning to add black opal to your collection, expect to spend at least $15,000.

Fire Opals

Fire opals can be either precious and rare, or a bit common and inexpensive.

True fire opals have red, orange, yellow and pink backgrounds, however, they aren’t always great at exhibiting play- of- color.

These are the ones that cost more, around $4000 for 10 carats, but some precious fire opal has sold for $10000 per carat!

Typically, however, the price ranges from $40-$500 per carat.

Fire opal is found in Mexico, but other origins include Ethiopia, Australia, Honduras and Guatemala.

How to factor in the setting cost

How you decide to use your opal is up to you, but you should seriously consider setting it in jewelry.

Unlike jade which has a hardness of 6.0-7.0, opal has a relatively low hardness of 5.5-6.5 on the Mohs Hardness Scale and is considered to have ‘poor wearability’.

Thus, the best approach is to pick the most suitable setting.

You wouldn’t want to go with a tension setting because this would cause it to wear easily.

You’ll also want to avoid faceting opal because the process to do so works against its nature.

You’re better off with protective settings like doublets and triplets, along with bezel settings, cage-type designs and raised prongs.

Pendants, brooches and other occasional wear jewelry are excellent choices.

Along with how much opal is worth, or the price of the opal, the setting cost is influenced by:

  • The materials/metals- Precious metals like gold and platinum will cost more than sterling silver or nickel. Factor in other materials used in the setting process.
  • Man hours- Use an appropriate metric for craftsmanship, jewelry designing, cutting fees, polishing, etc.

How to care for your opal jewelry

Opals are very sensitive gemstones, so like pearls, you’ll want to take a bit of extra care when dealing with opal jewelry.

Here are some tips that will ensure you get as much time as possible with your opal piece(s):

  • Never submerge your opal jewelry in water, even if it’s made of a resistant metal like gold or sterling silver.
  • Keep your opal cool, never exposing it to heat or low humidity. This can cause crazing and pits to form in the stone.
  • Try not to drop your opal jewelry because the impact can affect the stone.
  • Store your opal in a cool, dry place, preferably a jewelry box. If the external temperature is harsh, place a damp cotton ball around the opal to prevent moisture loss.
  • Avoid cleaning your opal with an ultrasonic cleaner or harsh chemical. Instead, wipe with a soft cloth.

Final words

Did you know that no two pieces of opal are identical? That means you’d be the only one in the world with an opal that is exactly like yours.

And, if you were born in September, great news: opal is one of your birthstones.

Opal is quite a fascinating gemstone and it’s easy to become an opal-holic!

With its wild color range, unique 3D aspect and purported benefits, it should be no surprise that opals can have such a large price range.

There’s something for everyone, and even if you can’t afford a rare black crystal opal, you can certainly get your hands on a stunning, one-of-a-kind natural opal.

How much is opal worth: FAQs

Are opals valuable?

Precious opals are considered valuable.

Is opal worth more than diamond?

It can be, especially rare colors like black.

What color opal is most valuable?

Black opals are the most valuable color.

How much is opal worth today?

Opal can sell for as little as $7 per carat, up to as much as $10,000 per carat, depending on the type of opal