Gemstone Treatments
All about gemstone treatments including heating, bleaching, surface coating and more.
Sapphire Treatment: The Complete Guide
Discover how ancient wisdom and modern science transform ordinary sapphires into extraordinary gems through four powerful enhancement techniques that may...
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Zircon Heat Treatment
Are zircons natural gemstones? Learn how zircon heat treatment works and the difference between zircon and cubic zirconia.
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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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