Ammonite Mining in Canada

Sapphire Mining in Montana

Does Synthetic Jade Exist?

The basic building blocks of understanding the science of gemstones.

Gem Formation: How are Gemstones Created?

Gemstone Hardness and Wearability

A Guide to Gem Classification

An Introduction to Gemology

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

10X Loupe for Gemologists and Jewelers

Refractometer Guide, Part 1: Refractive Index Testing

Spectroscope Instructions for Novice Gemologists

Gemology Tools

Learn about gemstone color, crystallography, hardness, chemical makeup and more.

Gemstone Physical Properties

Gemstone Color Measurements and Specifications

What is Gemstone Cleavage?

Physical and Optical Properties of Gemstones

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

An Introduction to Gem Identification

Gem, Mineral, and Rock Scanner Identification Apps Review

Identifying Opal Patterns

Gemstone Testing and Identification

Learn what a synthetic gemstone is and what the difference is between synthetics, treatments and imitations.

What's the Difference Between Synthetic, Simulated, and Created Gemstones?

Identifying Lab-Made Emeralds

Synthetic Gemstone Inclusions

Synthetic Gemstones

All about gemstone treatments including heating, bleaching, surface coating and more.

Disclosing Enhancements: A Gemologist's Guide

Common Gemstone Treatments Cheat Sheet

Aquamarine Color and Heat Treatment

Gemstone Treatments

Advanced gemology topics on a wide variety of technical subjects such as gemstone treatments and inclusions.

Impurity Ions and Gemstone Colors

HPHT Diamond Treatments

Gemstone Photomicrography: Photographing Inclusions

Advanced Gemology Topics

Gemstone history, legend, lore and other fun, non-technical articles.

Garnet Symbolism

The World’s Largest Emeralds

Ten Gemstones Rarer than Diamond

The Lighter Side of Gemology

Take a virtual trip to see where gemstones are found all over the world.

Top Spots for Gem Hunting in the US

Opal Prospecting and Mining

Desert Prospecting: Discovering California Turquoise

Gem Tourism

Questions from consumers and novice gemologists about all things related to gemstones and jewelry.

Is Lab-Created Alexandrite Real Alexandrite?

Ruby and Sapphire Survey: Where Do You Draw the Line?

Is Uranium Glass Safe to Facet?

Questions About Gems and Jewelry

Commonly used charts for gemology and jewelry and lapidary.

Gemstone Toxicity Table

Table of Refractive Indices and Double Refraction of Selected Gems

Specific Gravity Values of Selected Gems

Reference Charts & Materials

Science, tools, identification, treatment, valuation & grading of gems.

Gemology

An Interview with “Diamond Wizard” Maarten de Witte: Part 4

Jade Engagement Ring Guide

An Interview with “Diamond Wizard” Maarten de Witte: Part 2

Learn about the metal settings used in fine gemstone jewelry.

Jewelry Nomenclature: Jewelry Attachments and Various Findings

Choosing the Right Jewelry Settings for Your Gems

Protective Gem Settings for Rings

Jewelry Settings

Learn about the various types of precious metals used in gemstone jewelry including rings, necklaces and more.

Jewelry Metals 101: Gold, Silver, and Platinum

Testing Gold Karatage and Interpreting Marks

How to Calculate the Gold Markup for Jewelry

Jewelry Metals

Learn about the tools used in the settings and other metal components of gemstone jewelry.

Jewelry Making Tools: An Introduction

What Kinds of Soldering Surfaces are Used in Jewelry Making?

Flex Shaft Options for Jewelry Making

Jewelry Making Tools

How to take gemstones and set them into pieces of jewelry. Including rings, necklaces, bracelets and more.

Tips and Tools for Handling Gems Securely

Prong Setting Gems: A Beginner's Guide

Money-Saving Ways to Clean Jewelry

Metalsmithing and Jewelry Making Techniques

Learn about the issues facing the professional jewelry business.

Jewelry Business Advice

Trends and styles of gemstone jewelry with many examples to be inspired by.

37 Blue Gemstones (Names, Pics, & More)

Combining Stones in Jewelry

10 Rare Engagement Ring Stones that Won’t Break the Bank

Jewelry Styles and Inspiration

Evaluating antique gemstone jewelry and examples of different styles of gemstone jewelry from various eras.

Early History of Jewelry: Ancient Times to the 17th Century

Antique Engagement Rings

Lapidary Technology Through the Ages: Laps and Polish

Antique Jewelry and Jewelry History

Birdseye view of the cuts, tools and techniques involved in lapidary arts, i.e. cutting or forming gemstones.

A Guide to Gem Cutting Styles

Lapidary Fundamentals: Cutting Rough Stones

Lapidary Fundamentals: Cabochon Cutting

Fundamentals of Lapidary

Learn to facet. Articles for beginners who are just getting started in lapidary.

Gemstone Faceting Terms: A Glossary for Students

Faceting Equipment Essentials

Dopping with Wax: Getting Started

Beginner's Information - Learning to Facet

Learn about the tools and equipment involved in lapidary arts.

Lapidary and Faceting Equipment

How-to articles on a wide variety of faceting techniques.

Lapidary and Faceting Guides, Tips and Instructions

How to re-cut, re-polish and repair gemstones to bring out their best qualities.

Re-Cutting, Re-Polishing, and Repairing Gemstones

Clubs and trade shows for gemologists, jewelers and lapidaries.

Lapidary Clubs and Shows

What to consider when considering buying rough gemstones and how to decide what cutting technique is best.

Buying, Cutting and Evaluating Rough Gemstones

Articles about the business-side of lapidary arts as well as jewelry making and/or selling.

Resources for the Professional Lapidary

Tips and tricks for cutting, faceting and recutting specific types of gemstones.

Cutting Information for Specific Gemstones

Diagrams for use in faceting a wide variety of gemstones.

Gemstone Faceting Diagrams and Technical Cutting Information

Advanced questions about jewelry making and lapidary techniques.

Questions About Lapidary and Jewelry Making

How to grade colored gemstones and diamonds including using the 4Cs --Color, Clarity, Cut, and Carat Weight.

A Consumer's Guide to Gem Grading

An Introduction to Gemstone Grading

Clarity Grading for Colored Gemstones

Grading Gemstones and Diamonds

How to price or obtain the value, price and appraisal of a gem or piece of gemstone jewelry.

Appraising Gems and Jewelry

Are Diamonds Really Rare? Diamond Myths and Misconceptions

Advice for Determining Gemstone Value

Determining Gemstone Value, Price, and Appraisals

Detailed gem buying guides with example pictures and gem prices. Covers color, clarity, cut, carats, origin, values, wholesale and retail prices, and more.

Gem Buying Guides

Commonly used charts and table for jewelers, lapidaries and gemologists.

Cutting and faceting stones, jewelry settings, metals, tools and techniques.

Jewelry and Lapidary

International Gem Society

<p>The IGS Gem Price Guide covers commonly traded colored gems as well as more unusual, collectible gems. Prices are retail in US dollars. Unless otherwise noted, all prices are for cut gems and all weights are in carats. <a href="https://www.gemsociety.org/article/how-to-use-price-guide/" data-wpel-link="internal">Learn How to Use Our Gem Price Guide</a></p>

Gem Price Guide

Library of information related to gemstones, gemology, gemstone jewelry information, reference charts, and lapidary information.

Learning Center - International Gem Society

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International Gem Society LLC

<div class="su-row"><div class="su-column su-column-size-1-2"><div class="su-column-inner su-u-clearfix su-u-trim">Our Gemstone Encyclopedia has information on over 300 gemstones, from traditional and popular jewelry standards to collector’s stones that rarely appear for sale. Each entry has photos and detailed information about the gem’s properties. Entries for jewelry stones also have price guidelines and discussions of their most important value factors.</p><p>Browse through our Gem Encyclopedia, search for a specific gem, or use our filters to find different types of gemstones.<br /></div></div><div class="su-column su-column-size-1-2"><div class="su-column-inner su-u-clearfix su-u-trim"><div class="su-accordion su-u-trim"><div class="su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed" data-scroll-offset="0" data-anchor-in-url="no"><div class="su-spoiler-title" tabindex="0" role="button"><span class="su-spoiler-icon"></span>What is a Gemstone?</div><div class="su-spoiler-content su-u-clearfix su-u-trim"><h3>What is a Gemstone?</h3><p>Gemstones are minerals that have been chosen for their beauty and durability, then cut and polished for use as human adornment. Of course, there are exceptions to this definition. <a href="https://www.gemsociety.org/article/pearl-jewelry-and-gemstone-information/" data-wpel-link="internal">Pearls</a> and <a href="https://www.gemsociety.org/article/amber-jewelry-and-gemstone-information/" data-wpel-link="internal">amber</a> are well-known gemstones but they’re not minerals. They have organic origins. People frequently wear <a href="https://www.gemsociety.org/article/opal-jewelry-and-gemstone-information/" data-wpel-link="internal">opals</a> as jewelry stones, but these delicate gems require a great deal of care. <a href="https://www.gemsociety.org/article/what-is-a-gem/" data-wpel-link="internal">Read this article to learn more</a>.<br /></div></div><div class="su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed" data-scroll-offset="0" data-anchor-in-url="no"><div class="su-spoiler-title" tabindex="0" role="button"><span class="su-spoiler-icon"></span>Can Any Gem be Worn as Jewelry?</div><div class="su-spoiler-content su-u-clearfix su-u-trim"><h3>Can Any Gem be Worn as Jewelry?</h3><p>All gemstones have something appealing about them, whether that’s their appearance, their symbolism, their rarity, or an unusual physical or optical property. However, not all gems make good jewelry stones. Some are just too fragile to wear. In the Gem Listings below, popular jewelry and collector’s stones will have Wearability grades noted in their entries. These can range from “Excellent” to “Display Only.” <a href="https://www.gemsociety.org/article/hardness-and-wearability/" data-wpel-link="internal">Read this article to learn more</a>.<br /></div></div><div class="su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed" data-scroll-offset="0" data-anchor-in-url="no"><div class="su-spoiler-title" tabindex="0" role="button"><span class="su-spoiler-icon"></span>What are Precious and Semi-Precious Stones?</div><div class="su-spoiler-content su-u-clearfix su-u-trim"><h3>What are Precious and Semi-Precious Stones?</h3><p>People have classified gems in many different ways. Traditionally, precious stones were the Big Four gemstones — <a href="https://www.gemsociety.org/article/diamond/" data-wpel-link="internal">diamonds</a>, <a href="https://www.gemsociety.org/article/emerald-jewelry-and-gemstone-information/" data-wpel-link="internal">emeralds</a>, <a href="https://www.gemsociety.org/article/ruby-jewelry-and-gemstone-information/" data-wpel-link="internal">rubies</a>, and <a href="https://www.gemsociety.org/article/sapphire-jewelry-and-gemstone-information/" data-wpel-link="internal">sapphires</a>. Semi-precious stones were everything else. Today, gemologists don’t use these terms because they imply that some gems are better or worth more than others. In fact, some so-called semi-precious stones would be worth far more than so-called precious stones. <a href="https://www.gemsociety.org/article/how-gems-are-classified/" data-wpel-link="internal">Read this article to learn more</a>.<br /></div></div><div class="su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed" data-scroll-offset="0" data-anchor-in-url="no"><div class="su-spoiler-title" tabindex="0" role="button"><span class="su-spoiler-icon"></span>Are Lab-Created Gemstones Real Gemstones?</div><div class="su-spoiler-content su-u-clearfix su-u-trim"><h3>Are Lab-Created Gemstones Real Gemstones?</h3><p>Lab-created or synthetic gemstones have the same optical and physical properties as their natural counterparts. They’re grown from the same chemical ingredients and under the same physical conditions as mined gems, except at a greatly accelerated rate. Lab-created gems aren’t fakes. For example, lab-created rubies are real rubies, but they&#8217;re not natural rubies. (They&#8217;re also far less expensive than their mined counterparts). <a href="https://www.gemsociety.org/article/how-gems-are-classified/#Natural,_Synthetic,_and_Imitation_Gems" data-wpel-link="internal">Read this article to learn more</a>.<br /></div></div><div class="su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed" data-scroll-offset="0" data-anchor-in-url="no"><div class="su-spoiler-title" tabindex="0" role="button"><span class="su-spoiler-icon"></span>Are Rare Gems More Valuable?</div><div class="su-spoiler-content su-u-clearfix su-u-trim"><h3>Are Rare Gems More Valuable?</h3><p>All gemstones are rare. Rough minerals with the right qualities for gem cutting make up a tiny percentage of mined material. However, some minerals form more rarely than others in nature, because they either require very specific conditions to form or contain elements that occur rarely on Earth. Nevertheless, that doesn’t necessarily mean rare gems are more valuable. Consumer demand plays a critical role in a gem’s value. Some rare gems are so little known there’s just no market for them. <a href="https://www.gemsociety.org/article/the-x-factor/" data-wpel-link="internal">Read this article to learn more</a>.<br /></div></div><div class="su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed" data-scroll-offset="0" data-anchor-in-url="no"><div class="su-spoiler-title" tabindex="0" role="button"><span class="su-spoiler-icon"></span>How Can I Learn More About Gemstones?</div><div class="su-spoiler-content su-u-clearfix su-u-trim"><h3>How Can I Learn More About Gemstones?</h3><p>The International Gem Society (IGS) offers several online courses for people interested in learning more about gemstones. If you’re interested in starting a career in the world of gemstones, our <a href="https://www.gemsociety.org/course/professional-gemologist/" data-wpel-link="internal">Professional Gemologist Certification Course</a> will give you the knowledge and skills you’ll need. You’ll learn the basics of gemology, the properties of gemstones, how to use essential gemology tools, and how to identify different gemstones.</p><p>If you’re interested in learning about a specific type of gemstone, the IGS also offers <a href="https://www.gemsociety.org/course-type/speciality-mini-courses/" data-wpel-link="internal">mini-courses</a> on a wide variety of popular gemstones, such as <a href="https://www.gemsociety.org/course/diamond-specialist/" data-wpel-link="internal">diamonds</a>, <a href="https://www.gemsociety.org/course/ruby-specialist/" data-wpel-link="internal">rubies</a>, <a href="https://www.gemsociety.org/course/sapphire-specialist/" data-wpel-link="internal">sapphires</a>, <a href="https://www.gemsociety.org/course/emerald-specialist/" data-wpel-link="internal">emeralds</a>, <a href="https://www.gemsociety.org/course/pearl-specialist/" data-wpel-link="internal">pearls</a>, and more. These are perfect for prospective gemstone buyers who want to learn more before making an expensive purchase.</p><p>If you’re a novice gemologist who wants to learn more about <a href="https://www.gemsociety.org/course/gemology-tools/" data-wpel-link="internal">gemology tools</a>, or someone interested in <a href="https://www.gemsociety.org/course/gemstone-investing/" data-wpel-link="internal">investing in gemstones</a>, the IGS has courses for you, too.</p><p>Check out <a href="https://www.gemsociety.org/courses/" data-wpel-link="internal">our full List of Courses</a> to learn more.<br /></div></div></div></div></div></div><style> .su-accordian { border: none !important; } .su-spoiler { margin-bottom:0px !important; } .su-spoiler-title { margin-bottom:0px !important; } </style>

Gemstone Encyclopedia

<div class="section lc-hero"><div class="wrap"><div class="one-half first hero-text"><p><img src="https://www.gemsociety.org/wp-content/uploads/2014/07/icon-lc-vines.jpg" /></p><h2>Welcome to the IGS Learning Center</h2></div><div class="one-half"><img loading="lazy" class="alignnone size-full wp-image-190" style="width: 250px;" src="/wp-content/uploads/2016/03/home-iphone-display.png" alt="home-iphone-display" width="500" height="722" /></div></div></div><div class="section grey-noise lc-featured-content"><h3 style="text-align: center; margin-bottom: 40px;">What can we help you learn today?</h3><div class="one-fourth first"><div class="lc-featured"><p><a class="lc-featured-img" href="/gemology/" data-wpel-link="internal"><img src="https://www.gemsociety.org/wp-content/uploads/2014/09/gem-study.jpg" alt="learn_gemology_icon" /></a></p><div class="lc-featured-header"><a href="/gemology/" data-wpel-link="internal"><br /></a></p><h4>Learn Gemology</h4><p>Science, tools, identification, treatment, valuation &amp; grading of gems.</p></div></div></div><div class="one-fourth"><div class="lc-featured"><p><a class="lc-featured-img" href="/article/gem-pricing-guide-sample/" data-wpel-link="internal"><img src="https://www.gemsociety.org/wp-content/uploads/2014/09/gem-setting.jpg" alt="learn_gemology_icon" /></a></p><div class="lc-featured-header"><a href="/gemology/" data-wpel-link="internal"><br /></a></p><h4>Gemstone Values</h4><p>Lookup the current retail and wholesale price of any gemstone.</p></div></div></div><div class="one-fourth"><div class="lc-featured"><p><a class="lc-featured-img" href="/jewelry-lapidary/" data-wpel-link="internal"><img src="https://www.gemsociety.org/wp-content/uploads/2014/09/misc-gems.jpg" alt="" /></a></p><div class="lc-featured-header"><a href="/jewelry-lapidary/" data-wpel-link="internal"><br /></a></p><h4>Jewelry &amp; Lapidary</h4><p>Cutting and faceting stones, jewelry settings, metals, tools and techniques.</p></div></div></div><div class="one-fourth"><div class="lc-featured"><p><a class="lc-featured-img" href="/gemstone-encyclopedia/" data-wpel-link="internal"><img src="https://www.gemsociety.org/wp-content/uploads/2014/09/gem-display.jpg" alt="" /></a></p><div class="lc-featured-header"><a href="/gemstone-encyclopedia/" data-wpel-link="internal"><br /></a></p><h4>Full List of Gems</h4><p>Detailed information for any gemstone you are interested in.</p></div></div></div></div><div class="section" style="text-align: center;"><div style="max-width: 600px; margin: 0 auto;"><h3>Take your passion for gemstones to a whole new level</h3><h4 style="font-weight: 300; color: #a4a4a4;">FOR AS LOW AS $3/MONTH</h4><p><a class="button cta" href="/membership/" data-wpel-link="internal">See Plans &amp; Pricing <i class="fa fa-diamond"></i></a></p></div></div>

<p>In 2012, Donald Clark retired and passed along stewardship of the IGS to Seth and Lisa Rosen.  Seth and Lisa were longtime members of the IGS.  Seth is a gem collector and active Internet entrepreneur, who had already spent a great deal of time in the custom jewelry business. He founded <a href="https://www.custommade.com/">CustomMade, the world’s largest online custom jeweler</a> and also operates <a href="https://www.ganoksin.com/">The Ganoksin Project, a technical resource website for bench jewelers and jewelry manufacturers</a>. Seth and Lisa felt strongly that the IGS needed to remain a cost-effective, accurate, and comprehensive resource for all those interested in gemology.  IGS is our passion, and it is a family business.</p>


Seth and Lisa Rosen

<p>The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters &#8220;CSM&#8221; after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff&#8217;s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book &#8220;Modern Faceting, the Easy Way.&#8221;</p>


Donald Clark, CSM IMG

<p>Jeffery Bergman, SSEF SGC, founder and director of <a href="http://www.primagem.com/">8th Dimension Gems</a> in Thailand, is an American gem dealer with more than 40 years of experience in gemstone and fine jewelry mining, cutting, wholesaling and retailing. His career has taken him to more than 50 countries and every continent except Antarctica. He has appeared on the BBC, CNN, NBC, ABC and GEO; and has been featured in Time, USA Today, National Geographic, Gems &amp; Gemology and Discovery Channel magazine. He is a regular guest speaker at gem lab seminars and gemological association conferences and universities.</p>


Jeffery Bergman, SSEF SGC

<p>Dr. Joel E. Arem has more than 60 years of experience in the world of gems and minerals. After obtaining his Ph.D. in Mineralogy from Harvard University, he has published numerous books that are still among the most widely used references and guidebooks on crystals, gems and minerals in the world.</p>
<p>Co-founder and President of numerous organizations, Dr. Arem has enjoyed a lifelong career in mineralogy and gemology. He has been a Smithsonian scientist and Curator, a consultant to many well-known companies and institutions, and a prolific author and speaker. Although his main activities have been as a gem cutter and dealer, his focus has always been education. <a href="https://www.joelarem.com/">joelarem.com</a></p>


Joel E. Arem, Ph.D., FGA

<p>Fatma Oya Borahan, GG, FGG has Graduate Gemologist and Diamond Diplomas from the Gemological Institute of America (GIA) the German Gemmological Association (DGemG) and Gemmological Association of Great Britain (GemA). <a href="http://birdamlasu.com/">birdamlasu.com</a></p>


Fatma Oya Borahan, GG, FGG

<p>Barbara Smigel is a GIA certified gemologist, facetor, jewelry designer, gem dealer, gemology instructor and creator of the well-regarded educational websites <a href="http://www.acstones.com">acstones.com</a> and <a href="http://www.bwsmigel.info">bwsmigel.info</a>.</p>


Barbara Smigel, PhD. GG

<p>Dr. Gerald Wykoff is GG (Graduate Gemologist), a CSM (Certified Supreme Master gemcutter), educator, and author of several gemology books. He founded the American Society of Gemcutters in the 1980s and served for more than 10 years as the editor of its monthly magazine, American Gemcutter.</p>


Dr. Gerald Wykoff GG CSM

<p>A geologist, environmental engineer and Caltech graduate, Addison&#8217;s interest in the mesmerizing and beautiful results of earth&#8217;s geological processes began in her elementary school&#8217;s environmental club. When she isn&#8217;t writing about gems and minerals, Addison spends winters studying ancient climates in Iceland and summers hiking the Colorado Rockies.</p>


Addison Rice

<p>The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as <a href="https://rockpeddler.com/product-category/instructional-materials/"><em>Gram Faceting Designs</em></a>.</p>


Jeff R. Graham

<p>Bear Williams, CG, FGA (Hon), is President and Laboratory Director at <a href="https://stonegrouplabs.com/">Stone Group Laboratories</a>. Bear travels to gem producing countries and treating regions researching the latest trends in gemology and visiting with other lab directors. On-site research allows him to keep abreast of new synthetics and treatments in the marketplace. He regularly meets with other gemological associations and labs, and together will present research findings, and discuss the latest nomenclature or laboratory issues relevant to the trade and consumers. Recognized as an expert in the field of digital spectroscopy, Bear operates UV-Vis-NIR, ED-XRF, FTIR, UV, and Raman Spectrometers.</p>


Bear Williams

<p>Cara Williams, FGA, is Vice-President and Senior Staff Gemologist at <a href="https://stonegrouplabs.com/">Stone Group Laboratories</a>. Cara is a fellow of the Gemmological Association of Great Britain (Gem-A). She has been a tutor for the prestigious Diploma in Gemmology course for the Gem-A in London for more than 15 years. Growing up in a retail jewelry family with a concentration in colored stones, Cara has been in the wholesale trade since 1986. She brings a lifetime of experience working with gems to the lab, her students, and many published articles.</p>


Cara Williams

<p>Kyrylo Gubariev, Graduate Gemologist (GG, AJP) is a gemologist with a passion for sharing his knowledge with fellow gem lovers. Originally from Ukraine, he is currently based in Bangkok, Thailand.</p>


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