Gemology Tools


From the humble loupe to microscopes, spectroscopes and more. Learn about the tools of gemology here.

The Microscope: A Guide for Gemologists

The Microscope: A Guide for Gemologists

Sometimes, microscopic inclusions are the only way to distinguish natural from synthetic gems. This makes the microscope an essential lab...
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Ruby and Sapphire Grading Tools

Ruby and Sapphire Grading Tools

What ruby and sapphire grading tools does a novice gemologist need? Learn how basic gemological equipment can help you identify...
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GemEx iLoupe Review

GemEx iLoupe Review

How does the GemEx iLoupe compare to a standard jeweler’s loupe? Our review tests the device and app, designed for...
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How to Build Pocket Crossed Filters for Gemstone Testing

How to Build Pocket Crossed Filters for Gemstone Testing

The crossed filters technique allows gemologists to detect chromium in gems. Learn how to build a portable device for conducting...
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Color Filters: Uses and Limitations for Gemology

Color Filters: Uses and Limitations for Gemology

A set of color filters can be helpful in the field and in the lab. Learn the limitations and uses...
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10X Loupe for Gemologists and Jewelers

10X Loupe for Gemologists and Jewelers

The 10X loupe is the gemologist's best friend. Learn how to examine gemstones for fractures, inclusions, color, and much more...
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Polariscope Guide, Part 3: Testing for Gemstone Twinning, Dichroism, and Crystal Strain

Polariscope Guide, Part 3: Testing for Gemstone Twinning, Dichroism, and Crystal Strain

You can use a polariscope to observe gemstone twinning, dichroism, and crystal strain. Test your ability to identify these and...
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Polariscope Guide, Part 2: Testing for Optic Figure and Sign

Polariscope Guide, Part 2: Testing for Optic Figure and Sign

Learn how to use a polariscope to find the optic figure and sign of a gemstone. This is an important...
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Polariscope Guide, Part 1: Testing Gemstone Refraction

Polariscope Guide, Part 1: Testing Gemstone Refraction

The polariscope is one of gemology’s simplest and most useful tools. With a little practice and our three-part polariscope guide,...
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Refractometer Guide, Part 3: Determining Optic Character and Recognizing Optic Effects

Refractometer Guide, Part 3: Determining Optic Character and Recognizing Optic Effects

Learn how to determine a gem’s optic character with a refractometer and identify optical effects you may encounter during gem...
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Refractometer Guide, Part 2: Cabochon Testing

Refractometer Guide, Part 2: Cabochon Testing

Sometimes, analyzing cabochon gems with a refractometer requires different techniques than those for faceted gems. Learn these cabochon testing methods....
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Refractometer Guide, Part 1: Refractive Index Testing

Refractometer Guide, Part 1: Refractive Index Testing

A gem refractometer is the best tool for refractive index testing. Learn how to use this instrument to conduct this...
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Product Review: GL SpectroLite

Product Review: GL SpectroLite

The GL SpectroLite is an inexpensive and easy-to-use tool that can help gemologists conduct spectroscope exams. Read our review to...
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Product Review: No Name Refractometers

Product Review: No Name Refractometers

Beware of cheap "no name” refractometers (and their distributors). These tools may not be suitable for gem identification. Read our...
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Product Review: Duplex II and Rayner Dialdex Refractometers

Product Review: Duplex II and Rayner Dialdex Refractometers

The Duplex II and Rayner Dialdex both make excellent refractometers for gemologists. How do they compare head-to-head? Learn more from...
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Product Review, Gem Lab Refractometer

Product Review, Gem Lab Refractometer

A refractometer is an important tool for gem identification. The Gem Lab refractometer is an inexpensive model that’s a good...
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Product Review, Achiever Microscope

Product Review, Achiever Microscope

A microscope is an essential tool for gemologists. The Achiever Microscope is an excellent choice at a good price. Read...
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Recommended Diamond Grading Tools for Novices

Recommended Diamond Grading Tools for Novices

Identifying diamonds requires the right equipment. Learn what diamond grading tools novice professionals or hobbyists need.
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What Happened to the GIA GemSet Color and Hue Wheel?

What Happened to the GIA GemSet Color and Hue Wheel?

The GIA GemSet offered plastic color masters for color grading gems. It's no longer in production. Software alternatives exist but...
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Gemstone Refractometer Mini-Quiz

Gemstone Refractometer Mini-Quiz

Test your knowledge of refractometer gem analysis with this mini-quiz. You can review material on any question you miss at...
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Learn to Use a Refractometer (Video)

Learn to Use a Refractometer (Video)

This refractometer tutorial video will show you how to find a gem's refractive index, birefringence, optic character, and other properties....
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Recommended Gemology Tools and Instruments

Recommended Gemology Tools and Instruments

Gemstone identification requires a good reference library and some basic gemology tools. Before you go shopping, learn more about what...
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How to Evaluate Diamond Symmetry

How to Evaluate Diamond Symmetry

How can you evaluate diamond symmetry without an expensive proportion scope? Learn how to build an inexpensive alternative tool that...
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Dichroscope Guide for Gemologists

Dichroscope Guide for Gemologists

The dichroscope is one of the most useful instruments a gemologist can have. Its primary purpose is to determine the...
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Learn to Use a Polariscope (Video)

Learn to Use a Polariscope (Video)

Taking polariscope readings can be challenging. In this tutorial video, you'll learn how to use this tool and which gems...
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The Spectroscope

The Spectroscope

The spectroscope is a fundamental gemological tool. Learn how to use it to identify gemstones based on their absorption of...
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Learn to Measure Specific Gravity (Video)

Learn to Measure Specific Gravity (Video)

Determining a gem's specific gravity is an important identification technique. Watch this tutorial video to learn how to measure this...
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Spectroscope Instructions for Novice Gemologists

Spectroscope Instructions for Novice Gemologists

The spectroscope is one of gemology’s principal tools. Our basic spectroscope instructions will teach you how to operate and calibrate...
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Learn to Use a Diamond Tester and Chelsea Filter (Video)

Learn to Use a Diamond Tester and Chelsea Filter (Video)

Some very helpful gemology tools are easy to use. Learn about the Chelsea filter, diamond tester, and other simple instruments...
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Learn to Use a Dichroscope (Video)

Learn to Use a Dichroscope (Video)

Not sure if your gem is pleochroic? This tutorial video will teach you how to use the dichroscope to determine...
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Learn to Use the Spectroscope (Video)

Learn to Use the Spectroscope (Video)

Taking spectroscope readings can be challenging. This tutorial video will teach you different techniques you can use to view a...
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Learn to Use the Microscope (Video)

Learn to Use the Microscope (Video)

Some student gemologists might be unfamiliar with the microscope. This tutorial video will demonstrate how this instrument can help you...
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Using a Reticle: A Guide for Gemologists

Using a Reticle: A Guide for Gemologists

When combined with optical instruments, a reticle can take fine measurements. Learn how gemologists use this tool for measuring lengths...
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Interview with Gemology Tools Expert Cara Williams

Interview with Gemology Tools Expert Cara Williams

What’s working in a gem lab like? Gemology tools expert Cara Williams talks about the challenges as well as the...
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Advanced Gemology Equipment

Advanced Gemology Equipment

Gemstone treatments and synthetics are becoming more sophisticated. Learn about the advanced gemology equipment that gem labs use to stay...
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How to Build a Multipurpose Microscope Stage for Gems

How to Build a Multipurpose Microscope Stage for Gems

A multipurpose microscope stage can help you move, view, and photograph gemstones under magnification easily from many angles. Learn how...
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Gemology Book Reviews: Careers

Gemology Book Reviews: Careers

Artists, lapidaries, and gem merchants all have stories to tell. Three very different books with varied perspectives explore the lives...
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Amateur Gemstone Faceting Volume 1: Book Review

Amateur Gemstone Faceting Volume 1: Book Review

Amateur Gemstone Faceting Volume 1 provides a much-needed modern introduction to faceting for novices. Learn how instructors and students alike...
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The Collector’s Guide to the Minerals of New York State: Book Review

The Collector’s Guide to the Minerals of New York State: Book Review

The Collector's Guide to the Minerals of New York State is ideal for both experts and hobbyists. Its information, organization,...
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Faceting Articles, Designs, & Pictures by Glenn Klein: Book Review

Faceting Articles, Designs, & Pictures by Glenn Klein: Book Review

In Faceting Articles, Designs, & Pictures, renowned faceter Glenn Klein shares his insights on gem facet designs and the history...
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“Genesis And Classification Of Agates And Jaspers: A New Theory” Book Review

“Genesis And Classification Of Agates And Jaspers: A New Theory” Book Review

“Genesis And Classification Of Agates And Jaspers: A New Theory” insightfully explains the formation of these gems and features beautiful...
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Gemology Reference Books: Reviews

Gemology Reference Books: Reviews

Whether you’re an expert or novice gemologist or collector, add these gemology reference books we’ve reviewed to your library.
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Build Your Own Gemology Tools

Build Your Own Gemology Tools

Are you a hobbyist or professional gemologist facing high equipment costs? Read our IGS series of articles that can help...
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The Optical Spectrum and the Spectroscope

The Optical Spectrum and the Spectroscope

The spectroscope is a device that separates white light into an optical spectrum of component colors that can aid in...
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Product Comparison, Polariscopes

Product Comparison, Polariscopes

Polariscopes are one of our most useful instruments. They come in a wide variety of prices and qualities. There are...
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Product Review, Diamond Calculator

Product Review, Diamond Calculator

There is a new piece of software available that will be of interest to many of you. It is called...
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Gemology Interactive Media Reviews

Gemology Interactive Media Reviews

Have the information of authoritative gemology books at the click of your mouse. Our gemology interactive media reviews showcase three...
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How to Build a Home Gemology Laboratory

How to Build a Home Gemology Laboratory

Learn what you need to set up a your own gem lab. You may be surprised to learn that this...
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