Gemstone Treatments
All about gemstone treatments including heating, bleaching, surface coating and more.
Turquoise Treatments and Synthetics Guide
Almost all turquoises receive enhancements for jewelry use. Learn how to identify the most common turquoise treatments and synthetic options....
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Spinel Treatments and Enhancements
Spinels are rarely treated, but gemologists should know how to detect spinel treatments. Learn about filling, heating, and diffusion.
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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
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
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
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
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
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 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
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, 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
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 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 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
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
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 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 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
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
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, 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
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?
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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