
Destructive Gemstone Tests: Acid Testing
Acid testing is a destructive procedure gemologists and mineralogists can use to determine if some pieces are real or fake. Learn how to perform this test safely.
3 Minute Read
Organic Gem Materials
Natural coral, shell, and pearl are carbonates. Since they release a protein smell from hot point testing, you can’t use that test to distinguish them from plastic imitations. However, you can identify them by observing their reaction to acid.
Acid Testing Warnings
This is a potentially dangerous procedure for both stone and tester. Exercise great care. Keep in mind that acid testing is a destructive test that should only be conducted as a last resort.
Always Add Acid To Water
AAA – Always Add Acid to water! Never the other way around. If you pour water in acid, it will boil and splash out of the container. The acid will burn metal, wood, skin, etc. Memorize the AAA rule.
Pearl Warning
Since there are nondestructive ways to separate natural pearls from their imitations, acid testing isn’t recommended for pearls.
Necklace Alert
When acid testing a strand of beads, make sure you don’t get any fluid on the cord. The acids used for identification will damage cords.
Do Not Use Full-Strength Hydrochloric
…Related Articles
Pearl Value, Price, and Jewelry Information
Coral Value, Price, and Jewelry Information
Lapis Lazuli Value, Price, and Jewelry Information
Understanding Gem Synthetics, Treatments, And Imitations, Part 4: Synthetic Gemstone Guide
Latest Articles
800 Years of Mogok: A Celebration in Tenuous Times
What is the Average Gemstone Faceting Yield?
Pyroxmangite Value, Price, and Jewelry Information
How to Identify Emerald Simulants and Synthetics
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.