Science, tools, identification, treatment, valuation & grading of gems.
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An Introduction to GemologyThe basic building blocks of understanding the science of gemstones.75 Articles
Gemology ToolsFrom the humble loupe to microscopes, spectroscopes and more. Learn about the tools of gemology here.48 Articles
Physical and Optical Properties of GemstonesLearn about gemstone color, crystallography, hardness, chemical makeup and more.18 Articles
Gemstone Testing and IdentificationAll about how to identify gemstones using a number of methods.36 Articles
Synthetic GemstonesLearn what a synthetic gemstone is and what the difference is between synthetics, treatments and imitations.15 Articles
Gemstone TreatmentsAll about gemstone treatments including heating, bleaching, surface coating and more.21 Articles
Advanced Gemology TopicsAdvanced gemology topics on a wide variety of technical subjects such as gemstone treatments and inclusions.18 Articles
The Lighter Side of GemologyGemstone history, legend, lore and other fun, non-technical articles.48 Articles
Gem TourismTake a virtual trip to see where gemstones are found all over the world.22 Articles
Questions About Gems and JewelryQuestions from consumers and novice gemologists about all things related to gemstones and jewelry.45 Articles
Reference Charts & MaterialsCommonly used charts for gemology and jewelry and lapidary.16 Articles
Ammonite Mining in Canada
Sapphire Mining in Montana
Does Synthetic Jade Exist?
Gem Formation: How are Gemstones Created?
Gemstone Hardness and Wearability
A Guide to Gem Classification
10X Loupe for Gemologists and Jewelers
Refractometer Guide, Part 1: Refractive Index Testing
Spectroscope Instructions for Novice Gemologists
Gemstone Physical Properties
Gemstone Color Measurements and Specifications
What is Gemstone Cleavage?
An Introduction to Gem Identification
Gem, Mineral, and Rock Scanner Identification Apps Review
Identifying Opal Patterns
What's the Difference Between Synthetic, Simulated, and Created Gemstones?
Identifying Lab-Made Emeralds
Synthetic Gemstone Inclusions
Disclosing Enhancements: A Gemologist's Guide
Common Gemstone Treatments Cheat Sheet
Aquamarine Color and Heat Treatment
Impurity Ions and Gemstone Colors
HPHT Diamond Treatments
Gemstone Photomicrography: Photographing Inclusions
The World’s Largest Emeralds
Ten Gemstones Rarer than Diamond
Top Spots for Gem Hunting in the US
Opal Prospecting and Mining
Desert Prospecting: Discovering California Turquoise
Is Lab-Created Alexandrite Real Alexandrite?
Ruby and Sapphire Survey: Where Do You Draw the Line?
Is Uranium Glass Safe to Facet?
Gemstone Toxicity Table
Table of Refractive Indices and Double Refraction of Selected Gems
Specific Gravity Values of Selected Gems
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