Can You Identify Gems Without Seeing Gemstone Colors?
Did you know most gem species can be distinguished without the element of color? Learn the role gemstone colors play in gem identification.
Price and Value: Factory-Cut vs Custom-Cut Gemstones
How does faceting affect gem value? Unique custom-cut gemstones command high prices. Learn how custom cutting compares to factory cutting.
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 to report your findings clearly.…
How to Build Pocket Crossed Filters for Gemstone Testing
The crossed filters technique allows gemologists to detect chromium in gems. Learn how to build a portable device for conducting this useful ID…
Peridot Buying Guide
Master peridot buying with our expert guide covering quality evaluation, pricing secrets, jewelry considerations, and top global sources for…
Helping Clients with Inherited Gemstones and Jewelry
Gem dealers are often their clients’ most trusted advisers on gem matters. Learn how to help your clients with inherited gemstones and jewelry.…
Grading Gem Carvings
Gem carvings are judged on material, workmanship, and artistry. Learn how to apply these criteria to a piece with our step-by-step guide.
Color Filters: Uses and Limitations for Gemology
A set of color filters can be helpful in the field and in the lab. Learn the limitations and uses of color filters for gemology.
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 gems.
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