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8 Factors Why Opal is Valuable (Prices for Different Types)

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Opal is a one-of-a-kind, highly valuable gemstone. Saying just “highly praised” and “extremely valuable” is not enough to describe how beautiful opal is. Its intriguing play-of-color bewitches a human. Opal rightfully occupies the central place in high-end jewelry. Why is it so valuable? What properties of opal make the price reach thousands of dollars per carat? Let’s dive into the magnificent opals’ flashes and find this out.

8 factors determine opal’s value. Color, play-of-color, pattern, clarity, brightness, country origin, and the absence of treatment are the main ones. Best opals are of black background color with colorful, bright, and evenly distributed play-of-color, free of any treatment, and of Australian origin.

Opals are more expensive than diamonds and gold! Australian black opal price can sometimes reach even $10,000 per carat (0,2 grams only!). It’s complicated to evaluate opal because every stone is unique.

What are the factors of opal value? Which color or type of flashes are preferable? Maybe the country of origin plays the first role? We are delighted to tell you about opal. Each property of the stone is a miracle. Let’s check them all!

Why Opal is Valuable?
Is Opal Valuable?

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Does Opal Have Any Value?

The Roman word opalus was synonymous with the precious stone. There is something valuable in an opal for sure. 

Opal is a highly valuable gemstone. It has a unique property of play-of-color, which any other gemstone doesn’t have. That is why it is highly prized and often used as a central stone in high-end jewelry. The top-quality black opals reach $6,000 per carat value, being more expensive than gold and diamonds.

At first, we need to start with the opal categories. The approach differs from the classical approach to mineral gemstones. Precise chemistry and structure don’t work here. 

Here are the main opal categories commonly used in the trade:

  • Black opal. Opal with black background color, which perfectly contrasts colorful play-of-color.
  • White opal. Opal with distinct play-of-color, where background color ranges from translucent white to medium gray.
  • Crystal opal. Where the background ranges from transparent to semitransparent.
  • Water opal. The background is similar to crystal opal; however, it shows faint play-of-color or no play-of-color at all.
  • Boulder opal. A very different type of opal, as it includes host-rock fragments, or matrix, as part of the finished gem.
  • Fire opal. An opal where background color ranges from transparent to translucent reds and oranges to yellows. It either can or cannot show play-of-color.
  • Other opal types. There are a lot of other gem-quality opals. Some of them are non-phenomenal, which means do not have play-of-color. Opals can occur in pink, blue, and other colors, with high to low saturation and varying patterns.

How Can You Tell if an Opal is Valuable?

Opal is so mesmerizing that it’s hard to evaluate it from the first and even from the second glance. Further, we will try to abstract from the enchanting opal’s brilliance and deduce opal’s value factors.

There are 8 factors of opal value. Color, pattern, and clarity are the main ones. Valuable opal is that with black background color; play-of-color contains hues that range across the entire spectrum; fashes are big enough and evenly distributed in the whole gemstone; without any inclusions or fractures.

There is a list of factors that are used to determine opal value. They are slightly different in Australia and The United States. Even though, there are the main factors similar for the traders and apprisers from all over the world.

  1. Color

The color factor is probably the main one. It is subdivided into the background color and play-of-color. Dark background colors like black or dark blue are the most desirable as they create a contrast to the play-of-color phenomenon. 

The rarest play-of-color contains hues that range across the entire spectrum. Red is often considered the most desirable play-of-color hue. It is also important which colors of flashes are located together. Red which is next to blue, is a highly valuable combination.

  1. Pattern

The pattern is a way of play-of-color arrangement. Common terms for play-of-color patterns include:

  • Pinfire or pinpoint: small, closely set patches of color;
  • Harlequin or mosaic: broad, angular, closely set patches of color;
  • Flame: sweeping reddish bands or streaks that shoot across the stone;
  • Peacock: mainly blue and green.

Large, closely arranged patches of color are preferable over tiny, scattered dots. As with any play-of-color, no matter what the pattern, colors must be bright for the stone to be valuable.

  1. Clarity, transparency, and a number of inclusions

An opal’s clarity can range all the way from completely transparent to opaque. A cloudy or milky background color negatively influences the value of an opal. 

Opal is a mineraloid, with the next chemical formula SiO2*nH2O. We can see from the formula that opal has water in its composition. Opal contains up to 20% water trapped in its silica structure.

When it is subjected to heat or constantly exposed to the sunlight, opal can dry out, leading to tiny fracture formation. Crazing – the network of tiny fractures that develops when an opal loses moisture. These fractures lower the value of the gemstone. In more diversified lists of opal’s value factors, the next criteria can be included:

  1. Brightness

Australian opal association takes into account 7 subdivisions of brightness from the brightest  B1 to the dullest B7. The brighter the opal, the more expensive will be its value.

  1. Shape

Opal is almost always cut en cabochon. A cabochon stone is more valuable when it has a high dome compared to a flat stone. This is because cabochons make ideal ring stones, but flat stones are less desirable as they cannot be used in many jewelry designs.

  1. Country origin

Australia has a worldwide reputation as the world’s most expensive opals. Many countries like Ethiopia, Mexico, and Brazil produce good opals. Each country’s opals may be unique, and this factor helps determine the opal price.

  1. Opal field source

In the trade, certain mines have a reputation for producing good quality rough that makes excellent stones. This happens in Australian and Ethiopian opal fields. 

  1. Natural or treated

Opals are porous, so can be easily treated to enhance such quality as a background color. Sometimes opals can be assembled to produce triplets and doublets. All of these should be properly disclosed. Treatment decreases opal value.

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Why is Opal Worth So Much?

Opal is a rare gemstone because its formation requires a very specific environment. Opal is worth so much because of its unique play-of-color phenomenon, which cannot be observed in any other gemstone. Opal is so costly because every stone has its exclusive pattern. There are no two similar opals.

TIP: Correctly cutting and polishing opals brings beauty and exceptional color flash. Find out the step-by-step guide on how to cut and polish opals in the article below:
How to Cut & Polish Opals: Follow These 9 Simple Steps

How to Determine Opal Value?

How to Determine Opal Value?
How to Determine Opal Value?

The Opal value is determined by a list of factors. The main is color. The most valuable background is black. Play-of-color patterns should have large and bright sparkles of different colors, which are evenly distributed. Valuable opal has no inclusions or cracks. Opal should be free of any treatment.

Here is a brief step-by-step description of how to determine opal value:

  1. To tell if the opal is valuable or not, try to pay attention to its dominant background color. Black or any dark background colors are highly valuable as produce appealing contrast to the play-of-color phenomenon.
  1. The second step is to understand which color is prevalent in play-of-color sparkles. Red is the most valuable, while greens and blues tend to be the least valuable. Also, concerning the play-of-color phenomenon, check the distribution, contrast, and abundance. The most valuable samples have an even distribution and high contrast of colorful flashes. 
  1. The third step is transparency evaluation. High transparency is desirable in crystal opal but tends to reduce the value of black opal. Check for pits or blemishes visible on the top of the gem because they strongly detract from value. Check for signs of poor durability, like cracks, flaws, or cloudy areas. Look for signs of crazing by holding the opal up to a light source.

Opal Value (Price) per Different Units

The price for opal can be described in the next span: from $10 – 6,000 per carat. Exceptional Australian black opal commands the highest prices – up to $10,000 per carat. Rough opal prices are usually expressed in grams, pounds, and kilos. A kilogram of opal rough starts from thousands of dollars.

UnitsOpal Value
per carat $10 – 6,000
Black opals weighing 5-10 carats can cost up to $50,000.
per gram$50 – 30,000 
per ounce$1,400 – 840,000
per pound*rough opal$1,000 – 52,200
per kilo*rough opal$2,000 – 100,000
Opal Value (Price) per Different Units

TIP: When we hear a rare gemstone collocation, we immediately imagine a sparkling diamond on a velvet pillow. But it’s just a huge misconception. Check out the real rarest gemstones in the article below:
13 Rarest Gemstones on Earth: You will be Shocked!

Opal Value (Price) per Different Colors

Black-colored opal is in the highest demand. The price for black opal starts from $60 per carat (0.2 grams) and reaches up to $10,000 per carat. Common white opal can be purchased for $10-150 per carat. Blue and pink Peruvian opals’ value range from several dollars to many tens of dollars per carat.

Color of OpalPrice
Blackstart from $60 per carat
(occasionally reach $6,000 -10,000 per carat for truly exceptional stones)
White$10 – 150 per carat
Fire$40 – 500 per carat
Blue$7 – 300 per carat
Pineapple*For example, a sample 86 x 76 x 53mm, 1000 carats cost $15,000
The price for the sample can reach up to $500,000.
Red$10 – 200 per carat
Rainbo$10 – 1,000 per carat
Pink $7 – 300 per carat
Green$10 – 200 per carat
Opal Value (Price) per Different Colors

*it’s not a yellow color opal, it is a form of occurrence

Opal Value (Price) per Places of Origin

The mast valuable opal is considered to be Australian. Australian opal’s price ranges from $10 – 6,000 per carat, occasionally reaching $10,000 per carat in the case of exceptional black opals. Fire Mexican opals’ price points range from $7 – 300 per carat. Ethiopian opals are also quite expensive.

Place of OriginOpal Value
Australia$10 – 6,000 per carat.
Black Australian opal can reach $10,000 per carat for top-quality stones.
Ethiopia$5 – 250 per carat
Oregon (the USA)$3 -10 per gram
Louisiana (the USA) $3 – 20 per carat
Brazil$10 – 200 per carat
Mexico$40 – 500 per carat
Peru$7 – 300 per carat
Opal Value (Price) per Places of Origin

Where to Buy Real Opal Stones?

The best option to buy real opal is to visit some local stores near the opal deposit. It is the best chance to buy rough opal for the best price. Buy opals from companies that concentrate on opals only and do not retail other gemstones. Ask for a certificate. It will protect you from buying fakes.

TIP: To make the opal affordable to a wider range of people, a lot of different fakes have been created. Check out the main differences between real and fake opals in the article below:
Real vs. Fake Opal: Focus on These 6 Differences

FAQ About Opal Value

Sill did not find the answer to your answers about opals value? Find frequently asked questions in the section below:

Is Opal Worth More than Diamond?

Everything depends on the quality of both diamond and opal. However, sometimes high-quality opal’s price reaches several thousand dollars per carat (0.2 grams). Black Australian opals are worth up to $10,000 per carat, which is far more expensive than common diamonds.

Is Opal Worth More than Gold?

Opal is more expensive than gold, for sure. Today, the gold price is around $60 per gram, which is $12 per carat. At the same time, opal can be purchased from $10 to thousands of dollars per carat, and in exceptional cases, the material of the best quality reaches $6,000 per carat.

What color Opal is Most Valuable?

Black opal is the most valuable type of opal. A single black opal of exceptional quality can sell for tens of thousands of dollars. Black Australian opals are truly exceptional and the highest prices reported are $10,000 per carat for out-of-this-world stones.


Opal covers the whole spectrum of colors, all the way from completely transparent to opaque. Dramatic variation in color and types of play-of-color phenomenon makes opal a hard gemstone for value determination.

Consequently, opal prices also are hardly predictable. For example, rough common opal can cost just a few dollars per gram, while top-quality Australian black opals command prices up to $10,000 per carat (0,2 grams).

Here is a list of main opal value factors:

  1. Color (background color and play-of-color).
  2. Pattern.       
  3. Clarity, transparency, and a number of inclusions.
  4. Brightness. 
  5. Shape.
  6. Country origin.
  7. Opal field source.
  8. Natural or treated.

TIP: Opals are among the most beautiful gemstones you can find in nature. Check out the best locations for finding opals in the United States in the article below:
4 Best Locations for Finding Opals Near Me (United States)