All about how to identify gemstones using a number of methods.

Destructive Gemstone Testing

Destructive gemstone testing, done carefully, can help gemologists with difficult gem identifications. Learn the right techniques with our 5-part series.

Apatite specimen - gem scratch testing
Destructive Gemstone Tests: Scratch Testing

Gemstone scratch testing can help determine the Mohs hardness value of a mineral sample. Learn how to conduct this destructive gem test safely.

Destructive Gemstone Tests: Streak Testing

Streak testing is a destructive gemstone test rarely used by gemologists.  Most gems leave no streak.  Learn which gems do and what color they leave.

Coral - hot point testing
Destructive Gemstone Tests: Hot Point Testing

Gemologists use the hot point test to determine if a piece is a plastic imitation or coated in wax.  Learn more about this destructive test here.

Destructive Gemstone Tests: Acid Testing

Acid testing is a destructive procedure gemologists can use to determine if some pieces are real or fake. Learn how to perform the test safely here.

Dye Testing - Turquoise
Destructive Gemstone Tests: Dye Testing

Gemologists can use dye testing to determine if a gemstone has been dyed to alter its color. Learn how to perform this procedure safely here.

Difficult Gemstone Separations

Two of the trickiest gemstone separations to make are scapolite from citrine and apatite from tourmaline. Learn some tips for distinguishing these gems.

synthetic diamonds - CVD
Identifying Synthetic Diamonds

Although making gem-quality synthetic diamonds costs more than mining, some lab methods can yield gem-grade materials. Learn to identify these synthetics.

specific gravity testing - heat treated rubies
Specific Gravity Testing Part 1: Definitions

Learn the specific gravity testing methods critical for gem identification. Start here with the basics and key definitions.

synthetic gems - pulled alexandrite
Identifying Synthetic Gems

Distinguishing between natural and synthetic gems is a critical skill for gemologists. Learn about gem making processes and the telltale signs they leave.

Gem Testing Procedures

Identifying gems is like detective work, and requires the use of various testing procedures to help you narrow down your list of suspects to just one gem.

Ultraviolet Testing And Gemstone Identification

Ultraviolet testing can be crucial for gemstone identification. Learn the basics of this technique as well as how to make your own UV viewing box.

gem identification quiz - green gem
A Gem Identification Quiz for Novice Gemologists

Getting lost in the data is very easy when you're learning to identify gems. Take this gem identification quiz and learn how best to conduct your tests.

The Art and Science of Identifying Gemstones

Gemology is both art and science. Learn how identifying gemstones combines traditional testing techniques, modern software, and deductive reasoning.

Identifying Inclusions Found in Natural Gems

Successful tips and guide in identifying Inclusions Found in Natural Gems. Read and learn several ways to identify inclusions found in natural gems here!

What is it? Gemstone Identification Quizzes

This series of What is it? quizzes will help you hone your gemstone identification skills.

leaded glass enhanced ruby set
Natural Rubies Clarity Enhanced with Leaded Glass

Natural rubies clarity enhanced with leaded glass have opened new markets and challenged easy detection. Learn how to identify these treated gems.

Identifying Inclusions Found in Enhanced Gems

When Identifying Inclusions found in Enhanced Gems, you have to be very careful when inspecting your stones. A clue is to find bubbles in the glue layer.

Conflicting Gemology Terms and Definitions

No one to date has a total inventory, or a complete database, of gems and all their properties. Gemologists need to be cautious about relying on any one data source.

using heavy liquids for SG testing - bromoform
Specific Gravity Testing Part 5: Using Heavy Liquids

Using heavy liquids to measure a gemstone's specific gravity poses some health hazards. Learn the techniques and precautions that gemologists take.

calcite with hematite inclusions - specific gravity testing techniques
Specific Gravity Testing Part 4: Refining Your Specific Gravity Testing Techniques

Factors like liquid temperature and inclusions can affect a gem's density reading. These specific gravity testing techniques can improve your accuracy.

Specific Gravity Testing Part 3: Calculating Specific Gravity with an Electronic Scale

Learn how to use an electronic scale for calculating specific gravity. A simple hanging basket accessory lets you weigh gems underwater.

FI - Hanneman specific gravity scale - balance scale
Specific Gravity Testing Part 2: Using a Balance Scale or a Hanneman Specific Gravity Scale

Using a balance scale to test specific gravity is a recommended practice in gemology. Learn to make your own scale or buy a Hanneman specific gravity scale.

How To Modify A Powder Scale for Specific Gravity Testing

Learn how to modify a powder scale for specific gravity testing. A handmade wire basket will make this easy-to-use scale a great tool for gemologists.

Gemstone Examination Lesson

Learning how to conduct a gemstone examination takes practice. Follow an expert gemologist step-by-step through tests of five unknown samples.