How Much Is Opal Worth: Price Guide

Opal is a unique and mesmerizing gemstone that has captivated people’s imaginations for centuries. Known for its incredible play-of-color, which is caused by the diffraction of light within the stone, opal is highly valued and sought after in the world of gemstones. But how much is opal worth? In this guide, we will explore the various factors that influence the value of opal, including its type, color, clarity, pattern, carat weight, cut and shape, and treatment. By understanding these factors, you can better determine the value of an opal and make informed decisions when purchasing or selling opals.

Types of Opals

There are several types of opals, each with its own unique characteristics and value. Some of the most well-known types of opals include:

  • Common opal: A more opaque and less valuable variety of opal that lacks the play-of-color found in precious opals.
  • Precious opal: Opals with a play-of-color, further divided into several subcategories:
    • White opal: Has a light body tone and is more common than black opal.
    • Black opal: Has a dark body tone and is rarer and more valuable than white opal.
    • Crystal opal: A transparent or semi-transparent opal with a play-of-color.
    • Boulder opal: Formed within ironstone boulders, often with a unique mix of opal and ironstone.
    • Fire opal: A variety of opal with a vivid orange, red, or yellow body color, often without play-of-color.
    • Ethiopian opal: A more recent discovery, known for its unique patterns and vivid play-of-color.

Factors Affecting Opal’s Value

A. Color

Color is one of the most important factors in determining an opal’s value. Opals are prized for their play-of-color, which is the result of light interacting with the microscopic silica spheres within the stone. The body tone of an opal, which is the underlying color of the stone, also plays a significant role in its value.

  • Black opals, with their dark body tone, are typically the most valuable, as their dark background makes the play of color more vibrant and visible.
  • White opals and crystal opals are generally less valuable than black opals, but can still be quite valuable if they exhibit a strong and vivid play of color.

B. Clarity

Clarity refers to the degree to which an opal is free from inclusions and other imperfections. Inclusions, such as sand, potch lines (non-play-of-color opal material), or other foreign materials can reduce the value of an opal, especially if they interfere with the play-of-color.

C. Pattern

The pattern of an opal’s play-of-color is another important factor in determining its value. Some patterns are more rare and more desirable than others. Examples of opal patterns include:

  • Pinfire: A small, closely spaced pattern of color
  • Harlequin: A large, mosaic-like pattern of color, often considered the most valuable
  • Rolling flash: Bands or waves of color that shift as the stone is moved

D. Carat Weight

Carat weight, which is the unit of measurement for gemstones, also plays a role in determining an opal’s value. Larger opals are generally more valuable, as they are rarer and can display a more impressive play-of-color. However, size should be considered in conjunction with other factors, such as color, clarity, and pattern, to accurately determine an opal’s value.

E. Cut and Shape

The cut and shape of an opal can have a significant impact on its value. A well-cut opal will maximize the play of color, making the stone more visually appealing and valuable. Common opal shapes include oval, round, and free-form. While traditional shapes like oval and round can command higher prices, unique free-form shapes can also be highly prized if they showcase the opal’s play of color effectively.

F. Treatment

Some opals undergo treatments to enhance their appearance and durability. Treatments such as impregnation with oil, wax, or resin can improve the stone’s clarity and stability, but may also reduce its value. It’s essential to understand whether an opal has been treated and how that treatment may affect its worth.

Opal Pricing

A. Price Ranges by Opal Type

The price of an opal can vary greatly depending on its type and quality. Here are some average price ranges per carat for different types of opals:

  • Common opal: $10 – $50
  • White opal: $50 – $200
  • Black opal: $200 – $10,000+
  • Crystal opal: $100 – $1,000+
  • Boulder opal: $100 – $2,500+
  • Fire opal: $50 – $500+
  • Ethiopian opal: $10 – $500+

These prices can vary depending on factors such as color, clarity, pattern, carat weight, cut and shape, and treatment.

B. Price Comparison to Other Gemstones

When comparing opal’s value to other popular gemstones, such as diamonds, emeralds, and rubies, it’s important to note that opal occupies a unique position in the market. While some high-quality black opals can command prices similar to those of high-quality diamonds, emeralds, and rubies, opals are generally more affordable and accessible to a wider range of buyers.

Tips for Buying Opals

A. Know the Type of Opal You Want

Understanding the differences between opal types and their respective values is crucial when making a purchase. Determine which type of opal best suits your taste and budget before shopping.

B. Check for Treatments

Ask the seller about any treatments the opal may have undergone, and be cautious of heavily treated stones, as they may have a lower value.

C. Buy from a Reputable Source

Purchasing opals from a reputable dealer or jeweler is essential to ensure you receive a high-quality, authentic stone. Look for businesses with positive reviews and a history of satisfied customers.

D. Consider Certification

For high-value opals, consider obtaining a gemstone certification from a reputable gemological laboratory. This can provide you with peace of mind and assurance of the opal’s quality and authenticity.


The value of opal is determined by a combination of factors, including type, color, clarity, pattern, carat weight, cut and shape, and treatment. By understanding these factors and following the tips provided in this guide, you can make informed decisions when buying or selling opals. Ultimately, personal preferences and budget should guide your choice, as the true beauty of an opal is in the eye of the beholder.


  • Nathan Collins

    Having spent years working in the landscaping industry, Nathan Collins has cultivated a wealth of knowledge about the natural world. He is committed to helping others appreciate the beauty in their backyards, whether it's through identifying rare rocks and minerals or crafting the perfect landscape.

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