Gemstone Testing and Identification


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

Distinguishing Common Jade Lookalikes

Distinguishing Common Jade Lookalikes

Our table comparing the properties of jade lookalikes with natural jade will help gemologists distinguish authentic jade from simulants.
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Destructive Gemstone Tests: Acid Testing

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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Destructive Gemstone Testing

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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An Introduction to Gem Identification

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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Destructive Gemstone Tests: 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...
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Gem, Mineral, and Rock Scanner Identification Apps Review

Gem, Mineral, and Rock Scanner Identification Apps Review

How accurate are gem, mineral, and rock scanner identification apps? Our review covers the strengths and weaknesses of over 20...
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How to Modify a Powder Scale for Specific Gravity Testing

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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Distinguishing Aquamarine Imitations

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

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

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

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

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 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

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

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

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

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 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

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

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

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

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

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

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 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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Identifying Garnets Simplified

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

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: 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...
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Destructive Gemstone Tests: Streak Testing

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

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

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

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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Identifying Inclusions of Specific Gems

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

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

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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Conflicting Gemology Terms and Definitions

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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