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Top Considerations Before You Buy Opal

Top Considerations Before You Buy Opal

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Top Considerations Before You Buy Opal

Nothing spells diversity like opals. Popular among European royalty, the gem continues to steal the hearts of designers looking to make a fashion statement or expand their jewelry collection. Thanks to their indefinite crystalline structure, opals can take any shape or color. But these variations make opal shopping complicated. Here’s what to consider before you buy opal.


Black opals cost more than other hues. Tones also come into play. For instance, black opals with lighter tones are considered grey and less valuable. Rare colors are more valuable. For example, oranges and reds are more desirable than violets and blues. Apart from background hues, consider the gem’s play-of-color. This optical phenomenon occurs when light leaves the stone with flashing spectral hues.

Prized opals show play-of-color across the whole stone instead of one side. Patterns inside the play-of-color are also uncommon. While every play-of-color leaves patterns, some designs are more noticeable, hence, more desirable. Rare patterns include sunbursts, jigsaw, peacock, block, and starbursts. On the other hand, large flashes and sweeping patterns are more common and less desirable. This goes together with transparency. Gems cost more if the play-of-color occurs deeper in the stone. That’s especially true for lighter tones. Most importantly, pick a color you like and one that complements your skin tone.


It’s the amount of light returning to your eyes from the birthstone. Brightness depends on the surface and play-of-color. Bright opals cost more than dull ones, regardless of size and background color rarity. The brightness scale has seven levels, namely:

  • B7: The brightness is very weak. You need to view the gem under sunlight for hints of color. 
  • B6: The play-of-color remains weak under sunlight and artificial lighting. 

  • B5: The gem is not very bright. Some play-of-color is visible under artificial lighting and sunlight.

  • B4: The gem is bright. The play-of-color occurs under sunlight and artificial lighting but disappears in the shade.

  • B3: The stone is very bright. The play-of-color occurs under weak artificial light, sunlight, even the shade.

  • B2: The gem is brilliant. This intense play-of-color continues under the sun’s glare, artificial, and dim lighting.

  • B1: The birthstone is exceptionally brilliant. As such, it produces electric reflections and a rich play-of-color despite the amount of lighting.


Though they reduce the gem’s value, natural imperfections help you buy otherwise unaffordable stones. What’s more, the flaws prove the gem isn’t man-made. For instance, white or cream patches indicate clay traces during the gem’s formation.

While potch lines are acceptable, ensure they don’t contrast the opal’s appearance. Note that potch lines affect the stone’s value. Additionally, don’t purchase a cracked gem. Although they can polish the stone to preserve its value, jewelers should mention whether a gem has undergone repairs, stabilization, or treatment before you buy opal. Dry the gem and view it under sufficient lighting to check for flaws.


Ordinarily, the stone’s rough form determines its shape. However, opals may be polished into particular shapes to retain yield and a deeper color bar. Color bars are regions on the stone that determine the play-of-color.

Thin color bars may command higher prices, but they’re harder to set, thus, less desirable. Common shapes include oval, round, teardrop, rectangle, and square. However, you can make your jewelry unique with freeform pieces. Freeform opals lack defined detonations. These stones can either have uneven or symmetrical shapes.

Contact Us for Assistance

Buying opals is hard as a beginner. But engaging professionals, like the experts at Ralph Mueller & Associates, can help inform you about best practices. For more information, contact us today.