Gemstone Testing and Identification
All about how to identify gemstones using a number of methods.
Distinguishing Aquamarine Imitations
How can gemologists quickly distinguish aquamarines from aquamarine imitations? We’ll review some common lookalikes and their most notable differences.
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Identifying Synthetic Gems
Distinguishing between natural and synthetic gems is a critical skill for gemologists. Learn about gem making processes and the telltale...
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Emerald Myth Busters: Identifying Colombian Stones
Colombian emeralds can command premium prices. Jeffery Bergman separates emerald myth from fact when it comes to determining the origins...
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Difficult Gemstone Separations
Two of the trickiest gemstone separations to make are scapolite from citrine and apatite from tourmaline. Learn some tips for...
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Identifying Synthetic Diamonds
Although most manufacturers disclose their synthetic diamonds, some resellers don’t. Learn how to identify these lab-created diamonds.
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Gemstone Identification Quizzes: Testing Procedures
Gemstone identification can involve many tests. These quizzes can help novice gemologists learn to pick the appropriate ones and identify...
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Buying Gems: Test Your Identification Skills
When buying gems, gemologists must temper their excitement with an analytical eye. Test your gem identification skills with these quizzes....
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Gemstone Visual Examination Quizzes
A visual examination is the first step to identifying a gemstone. These quizzes will help student gemologists learn to recognize...
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A Gem Identification Quiz for Novice Gemologists
Learning how to identify gems involves more than just data. This gem identification quiz can help novice gemologists learn how...
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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....
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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...
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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...
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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...
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Specific Gravity Testing Part 3: Calculating Specific Gravity with an Electronic Scale
You can use an electronic scale for calculating specific gravity if you have the right accessory, a hanging basket for...
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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...
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Specific Gravity Testing Part 1: Definitions
Learn specific gravity testing methods for gem identification. Our 5-part introductory series starts with the basics and key definitions.
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Enhanced Gem Inclusions
Gem treatments can affect a stone’s value and stability. Learn how the most common procedures work and how to identify...
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Ruby-Glass Composites vs Leaded Glass Clarity Enhancements
Ruby-glass composites and leaded glass ruby clarity enhancements are difficult for gemologists to detect. Learn how to identify these gems...
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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...
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Identifying Garnets Simplified
Identifying garnets by species is complicated. Learn how to use refractive index, hue, and absorption spectrum readings to simply the...
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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...
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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...
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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...
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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...
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Identifying Opal Patterns
Opal connoisseurs all have their favorite opal patterns. Learn how to identify the patterns of these beautiful gems with plenty...
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Opal Simulants: How to Spot Imitation Opal
How can you be sure that a piece of opal for sale is genuine? Learn about the major types of...
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Eight Opal Types Explained
Opal is a complicated gemstone, and many factors affect its price. Learn how to distinguish these eight opal types and...
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An Introduction to Gem Identification
Gem identification is part detective work, part art. Learn how gemologists can distinguish gem species and determine whether a stone...
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Identifying Inclusions of Specific Gems
Some natural as well as synthetic gems have specific, characteristic inclusions. Learn the identifying inclusions of some of the most...
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The Art and Science of Identifying Gemstones
Learn how to identify gems using gemology tools and the Gemology Tools software, which makes it easier than ever to...
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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...
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Destructive Gemstone Testing
Destructive gemstone testing, done carefully, can help gemologists with difficult gem identifications. Learn the right techniques with our 5-part series....
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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...
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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...
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