How it Works: Recutting Gems to Maximize Value
Recutting gems that have been poorly cut can increase their value significantly. See how precision custom cutting can transform a gem.
Dopping with Wax: Getting Started
Novice gem faceters often have questions about dopping with wax. Learn what types of dopping wax to use and how to get started.
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 properties of…
A World of Crystals
We live in a world of crystals. Learn what they are and where you can find them, from deep underground to the dust in the air and even inside our bodies.…
Polariscope Guide, Part 3: Testing for Gemstone Twinning, Dichroism, and Crystal Strain
You can use a polariscope to observe gemstone twinning, dichroism, and crystal strain. Test your ability to identify these and other gem properties…
Polariscope Guide, Part 1: Testing Gemstone Refraction
The polariscope is an essential tool for gem identification. Learn how it works, how to use it, and how to test gemstone refraction.
Gem Formation: How are Gemstones Created?
Gem formation usually involves mineral crystallization and other geological processes. Learn how these affect the gemstone properties gemologists…
Cuprite Value, Price, and Jewelry Information
One of the rarest of all facetable gems, cut cuprites can show magnificent deep red color. However, these beautiful stones are too fragile for most…
Distinguishing Diamonds: Educating Your Eyes
Distinguishing diamonds from their lookalikes requires educated eyes. Learn what visual features to look for and the properties of many popular…
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