Gemstone Treatments


All about gemstone treatments including heating, bleaching, surface coating and more.

Disclosing Enhancements: A Gemologist's Guide

Disclosing Enhancements: A Gemologist's Guide

Disclosing enhancements to gems is a key duty for gemologists. Learn what are the hardest treatments to detect and how...
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Identifying Jade Treatments

Identifying Jade Treatments

Jade is one of the most popular and expensive gemstones. It can also receive many enhancements. Learn about jade treatments...
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Hybrid Gemstones: Glass Rubies and More

Hybrid Gemstones: Glass Rubies and More

Some gems contain both natural and lab-made components. Learn about these hybrid gemstones and how to distinguish them from mined...
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Pearl Treatments and Enhancements

Pearl Treatments and Enhancements

Did you know that routine pearl treatments are the most common enhancements in the gem trade? Learn more about these...
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Difficult Gemstone Separations

Difficult Gemstone Separations

Two of the trickiest gemstone separations to make are scapolite from citrine and apatite from tourmaline. Learn some tips for...
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Enhanced Gem Inclusions

Enhanced Gem Inclusions

Gem treatments can affect a stone’s value and stability. Learn how the most common procedures work and how to identify...
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Corundum Treatments

Corundum Treatments

Corundum gems receive more types of treatments than any other stones. Learn how to test rubies and sapphires for signs...
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How to Test for Diffusion Treated Gems

How to Test for Diffusion Treated Gems

Learn how to spot diffusion treated gems with a simple immersion test. This common treatment for sapphire can significantly reduce...
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Ouro Verde Quartz: History and Treatment

Ouro Verde Quartz: History and Treatment

Ouro Verde quartz, also known as lemon quartz, is a popular treated stone. Learn how experiments with other gems led...
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Aquamarine Color and Heat Treatment

Aquamarine Color and Heat Treatment

There's more to aquamarine color than blue. Most natural stones start blueish green and are heated to blue. Learn the...
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Quartz Color Treatments

Quartz Color Treatments

Quartz color treatment results vary due to the stone's origin. Learn the effects you can achieve with different materials and...
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Center-Fused Color Treated Gemstones

Center-Fused Color Treated Gemstones

Center-fused color treated gems are assembled from natural rough. Learn how the procedure works and how to identify this stable...
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A Beginner's Guide To Common Gemstone Heat Treatments

A Beginner's Guide To Common Gemstone Heat Treatments

Gemstone heat treatments can increase the beauty and value of many rough pieces. Learn how to conduct the most common...
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Gemstone Treatment Codes

Gemstone Treatment Codes

The AGTA has proposed the use of gemstone treatment codes to promote disclosure and a common language for these procedures....
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How Can Gem Buyers Protect Themselves from Fraud?

How Can Gem Buyers Protect Themselves from Fraud?

How can gem buyers avoid undisclosed gem treatments and substitutions? Learn why it's best to deal with expert gem cutters...
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Gemstone Coatings: CVD and More

Gemstone Coatings: CVD and More

Gemstone coatings are a simple way to enhance color and luster. Learn about commonly coated gems, different coating techniques, and...
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Common Gemstone Treatments Cheat Sheet

Common Gemstone Treatments Cheat Sheet

There are so many common gemstone treatments available today that keeping track of them can be difficult. This list and...
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Emerald Enhancements: A Consumer and Trade Guide

Emerald Enhancements: A Consumer and Trade Guide

Almost all cut emeralds have had clarity enhancements. Learn how these emerald enhancements work, what substances are used, and how...
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Emerald Treatments and Alternatives

Emerald Treatments and Alternatives

Emerald treatments, such as oiling, are very common. Learn what these techniques do, how emeralds are graded, and what gems...
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Opal Treatments: How to Detect Treated Opals

Opal Treatments: How to Detect Treated Opals

With so many opal treatments on the market, it’s important to understand the different enhancement processes. Read on to learn...
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Gem Treatment Survey: Is this Gem Natural?

Gem Treatment Survey: Is this Gem Natural?

We've tallied your opinions from our gem treatment survey. Are treated gems natural? How much should they cost? With a...
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