An Introduction to Gemology
The basic building blocks of understanding the science of gemstones.
How Do Zircons Form?
As a December birthstone, blue zircon is very popular. But are blue zircons natural? Learn how zircons form and get...
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What is Jedi Spinel?
Jedi spinel makes a beautiful jewelry stone. Learn how it got its name and what qualities make this vivid pinkish...
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How Do Turquoises Form?
Turquoise gems can show many beautiful variations. Learn how turquoises form and how geology affects their color, shape, and durability....
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A History of Silver Mining in the United States
Over six thousand years ago, the ancient Egyptians created beads made of silver and inscriptions indicate that it was worth...
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What are Balas Rubies and Ruby Spinels?
For centuries, balas rubies were prized by royalty. Learn what happened after gemologists identified these gems as red spinels instead....
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How Do Spinels Form?
Available in many colors, spinels are becoming more popular with consumers. Learn how spinels form and how these gemstones get...
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What are Cobalt Spinels?
Learn how gemologists identify cobalt spinels and what qualities you should look for when buying these beautiful, vivid blue gemstones....
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Jade Color Trade Names
Jade color trade names describe prized hues and patterns in jadeite and nephrite stones. Learn about the most popular and...
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Maw Sit Sit Guide
Learn everything you need to know about maw sit sit, a rare, vibrant green gem rock used to make beautiful...
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How Does Jade Form?
The minerals known as jade, jadeite and nephrite, appear similar but have different properties. Learn how these materials form geologically....
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Does Chrysoprase Jewelry Fade?
Should you wear chrysoprase jewelry only at night to protect the gem’s striking green color? Learn the facts here.
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Gemstone Care Guide
Our gemstone care guide covers many popular gems. Learn how best to maintain your gemstone jewelry and what kinds of...
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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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What are Lab-Grown Sapphires?
Learn how lab grown sapphires are made and how gemologists can distinguish natural from synthetic sapphires.
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Natural Pearls vs Cultured Pearls
Many consumers don’t understand the difference between natural pearls and cultured pearls. Learn what these terms mean and how to...
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A World of Crystals
We live in a world of crystals. Learn what they are and where you can find them, from deep underground...
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Top Spots for Gem Hunting in the US
Visit one of the top gem hunting spots in the US. Go alone or with the family. A gemology-themed vacation...
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Gem Formation: How are Gemstones Created?
Gem formation usually involves mineral crystallization and other geological processes. Learn how these affect the gemstone properties gemologists study.
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An Introduction to Gemstone Inclusions
Gemstone inclusions are materials trapped inside gems as they form. Learn how gemologists use inclusions to help identify gemstones and...
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What are Crystal Systems and Mineral Habits?
Crystals have habits. In crystallography, mineral habits refer to the way crystals form within a specific mineral. There are six...
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Gemstone Hardness and Wearability
Gemstone hardness measures resistance to scratching. A gem's wearability grade takes hardness into account, but it’s only one of many...
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Opal Wearability and Jewelry Tips
Are opals too delicate for jewelry? Learn how to choose the right settings for opal wearability, so you can enjoy...
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Guide to Organizing Your Gemstone Collection
Learn how to organize your gemstone collection. Choose the storage and display options that are right for you and create...
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Take the Birthstone Quiz
What do you know about birthstones? Take our short birthstone quiz and learn about the makeup, cutting, and value of...
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How to Start a Gem Collection
Although many gem enthusiasts want to become collectors, they may not know where to begin. Read this article for tips...
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Understanding Gemological Formulas
Gemological formulas identify the chemical composition of gems and minerals. Learn what the symbols, numbers, and parentheses mean.
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What is Gemstone Luster?
Gemstone luster describes how a gem's surface looks when it reflects light. Learn the common terms gemologists use for this...
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What is a Gem?
Even the most general definition of a gem has many exceptions. Learn what qualities have been used to identify gemstones...
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A Guide to Gem Classification
Gemologists use several different gem classification methods. Learn how the most common systems work and what they cover as well...
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What are Allochromatic and Idiochromatic Gems?
Learn the difference between allochromatic and idiochromatic gems and why some gem species can occur in many color varieties and...
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Mechanical Gemstone Cleaning
Mechanical gemstone cleaning has benefits and risks. Learn all about ultrasonic, steam, and boiling systems and how gems might react...
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What is Gemstone Dispersion?
Learn what gemstone dispersion means, what causes it, and how it relates to other optical effects.
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What are Gem Species and Gem Varieties?
Gem species are mineral species prized for their durability and beauty. Learn how chemical formulas and crystal structures define species...
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How Do Aquamarines Form?
The March birthstone, aquamarine is a popular gem. Learn how aquamarines form, what they look like, and how they get...
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Trapiche Gems: An Introduction
Satisfying the human desire for symmetry, trapiche gems have a special allure. Learn what makes these rarities so unique in...
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Understanding Gem Synthetics, Treatments, and Imitations, Part 5: Gemstone Treatments
Identifying gemstone treatments is difficult even for experienced gemologists. Learn about the many different ways gem color and clarity are...
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What is a Crystal?
Learn the scientific definition of crystal used by gemologists and answer some basic questions about what is and is not...
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What is a Gem Reflectometer?
What’s the difference between a reflectometer and a refractometer? If you’re interested in studying or buying gems, learn the facts...
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What are Gemstone Absorption Spectra?
Learn how gems absorb wavelengths of light and how gemologists use gemstone absorption spectra to identify gems. There’s more to...
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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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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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How Do Garnets Form?
A versatile gem and the famous January birthstone, garnet is a favorite among jewelers and consumers. Learn how garnets form...
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How to Clean Your Gemstone Jewelry
A little gemology goes a long way. Learn how to clean your gemstone jewelry safely and how to deal with...
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How Does Quartz Form?
Quartz is one of the most abundant minerals on earth. Learn how quartz forms and how its most popular varieties...
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How Does Topaz Form?
Topaz requires specific and unusual conditions to form. Learn how topaz develops and how it gets its colors, from yellow...
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How Do Tourmalines Form?
Learn about tourmaline formation, where tourmaline is found, and the unusual geological conditions that give this stone its fantastic colors....
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How Do Emeralds Form?
How do emeralds form? Learn how the emerald growth process works and why it makes these gems rare, green, and...
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What’s the Difference Between Rubies and Pink Sapphires?
How do gemologists distinguish between rubies and pink sapphires? Learn about the chemistry of corundum and the history of the...
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