All about gemstone treatments including heating, bleaching, surface coating and more.
Turquoise Treatments and Synthetics Guide
Spinel Treatments and Enhancements
Disclosing Enhancements: A Gemologist’s Guide
Identifying Jade Treatments
Hybrid Gemstones: Glass Rubies and More
Pearl Treatments and Enhancements
Difficult Gemstone Separations
Enhanced Gem Inclusions
How to Test for Diffusion Treated Gems
Ouro Verde Quartz: History and Treatment
Aquamarine Color and Heat Treatment
Quartz Color Treatments
Center-Fused Color Treated Gemstones
A Beginner’s Guide To Common Gemstone Heat Treatments
Gemstone Treatment Codes
How Can Gem Buyers Protect Themselves from Fraud?
Gemstone Coatings: CVD and More
Common Gemstone Treatments Cheat Sheet
Emerald Enhancements: A Consumer and Trade Guide
Emerald Treatments and Alternatives
Opal Treatments: How to Detect Treated Opals
Gem Treatment Survey: Is this Gem Natural?
When you join the IGS community, you get trusted diamond & gemstone information when you need it.
Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!