Advanced Gemology Topics


Advanced gemology topics on a wide variety of technical subjects such as gemstone treatments and inclusions.

Jade Sources

Jade Sources

Jadeite and nephrite occur all over the world. Learn about the most notable and productive gem-quality jade sources..
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How to Measure an OTL Gemstone Refractive Index

How to Measure an OTL Gemstone Refractive Index

Measuring “over the limit” (OTL) refractive indices can help distinguish diamonds from simulants. You can do this with a simple...
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Gem Origin Opinions: When Gemology Labs Agree to Disagree on Sapphire Origins

Gem Origin Opinions: When Gemology Labs Agree to Disagree on Sapphire Origins

Why do gemology labs sometimes have different gem origin opinions, especially for sapphires? Learn the science and history behind the...
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Emerald Origins: History and Identification

Emerald Origins: History and Identification

Emeralds from different sources can vary in quality. Learn how to identify emerald origins by analyzing the optical and physical...
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Aquamarine Sources

Aquamarine Sources

Aquamarines are popular gemstones and can be found in many areas worldwide. Learn about some prized varieties and the most...
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Gemstone Physical Properties

Gemstone Physical Properties

The optical properties of gems attract our eyes and can give a cut stone a unique character. However, gemstone physical...
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Gemstone Photomicrography: Photographing Inclusions

Gemstone Photomicrography: Photographing Inclusions

Explore the amazing world of gemstone photomicrography. These tips can help you view and photograph spectacular inclusions found inside many...
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Gemstones and Refraction Liquids

Gemstones and Refraction Liquids

Gemologists use refraction liquids to identify gemstone refractive indices (RI). Learn about the properties of these liquids and safe RI...
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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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HPHT Diamond Treatments

HPHT Diamond Treatments

HPHT diamond treatments can only be positively identified with costly equipment. However, you can learn to assess the probability that...
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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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Identifying Garnets Simplified

Identifying Garnets Simplified

Identifying garnets by species is complicated. Learn how to use refractive index, hue, and absorption spectrum readings to simply the...
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Gemstone Radiation Treatment

Gemstone Radiation Treatment

Gemstone radiation is a common but little understood technique for altering gem colors. Learn how it works and what gems...
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Impurity Ions and Gemstone Colors

Impurity Ions and Gemstone Colors

How do gems likes rubies and red beryls get their red color? Learn the role impurity ions play in the...
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Emerald Fillers and Treatments

Emerald Fillers and Treatments

Emerald fillers can improve the beauty of these gems but also have some drawbacks. Learn how to choose the right...
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Identifying Inclusions of Specific Gems

Identifying Inclusions of Specific Gems

Some natural as well as synthetic gems have specific, characteristic inclusions. Learn the identifying inclusions of some of the most...
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Shells and Sea Shells

Shells and Sea Shells

Sea shells are one of our most ancient decorations. Our prehistoric ancestors used to string them into necklaces or hang...
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Fossilized Organisms

Fossilized Organisms

Most people who have an interest in gemstones or nature have seen petrified wood, but fewer are aware of the...
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