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International Gem Society

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International Gem Society

Gemology Career Options

Thinking of becoming a gemologist? Consider these gemology career options, compare their estimated salaries, and decide which one may be right…

What is Gemstone Transparency?

Gemstone transparency describes how much light passes through a gem and how it scatters. Learn what causes a gem to be opaque, translucent, or transparent.…

Should I Buy a Diamond Online?

Do you want to buy a diamond for an engagement ring? Don’t. Still want to buy a diamond? OK. Here are the pros and cons of buying a diamond online.

Properties of Diamond Simulants

Diamond simulants, like cubic zirconia and moissanite, often appear in jewelry. See how the properties of real diamonds compare with popular…

A Brief History of Diamonds

Learn how diamonds formed geologically and how they became the virtual standard for engagement ring stones in this brief history of diamonds.…

Opal and Pearl Care Guide

Opals and pearls have special setting, cleaning, and storage needs. Our opal and pearl care guide will help you keep your jewelry beautiful.

What is Gemstone Birefringence?

Gemstone birefringence is a measure of a gem’s double refraction. Learn how it’s used to identify gems and see the effects birefringent gems…

Sapphire Buying Guide

Long associated with royalty, sapphires are some of the most popular (and expensive) gems in the world. Our sapphire buying guide will help you…

What is a Crystal?

Learn the scientific definition of crystal used by gemologists and answer some basic questions about what is and is not a crystal.

What is Gemstone Pleochroism?

Some gems show pleochroism, two or three different colors depending on the viewing angle. Learn why this occurs and how it helps gemologists identify…

Bead and Necklace Size Charts

Whether you’re a novice bead jewelry maker or just shopping for necklaces, these bead and necklace size charts and links to related articles…

Standard Gem Sizes Chart

Will your gem fit in a standard setting? Use this chart of standard gem sizes for popular cuts and also learn how to estimate gem weight based on size.…

Peridot Buying Guide

Our peridot buying guide can help you learn how these gems are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.…

Sphalerite Buying Guide

Our sphalerite buying guide can help you learn how these gems are graded, what to avoid, and how to identify a high quality stone or a bargain in the…

Opal Polishing Survey Results

Take a look at the IGS member survey results for opal polishing. You’ll find recommendations for polishes, laps, and techniques for handling these…

Peridot Polishing Survey Results

Popular jewelry stones, peridots can actually vary in hardness. Our IGS member survey results can help you choose the right tools and techniques…

Corundum Polishing Survey Results

The corundum gem family includes ever popular rubies and sapphires. Our IGS member survey results offer some corundum polishing recommendations.…

Quartz Polishing Survey Results

Looking for lap, polish, or lubricant suggestions for quartz polishing? You can find numerous combinations and technical advice in our IGS member…

What is my Birthstone?

The idea of a single birthstone for each month is a modern idea with a long history, but today’s consumers can choose gems from traditional or modern…

Chrome Tourmaline Buying Guide

Rare chrome tourmaline can show an emerald-like green color. With a highly desired color and tourmaline’s excellent jewelry stone qualities,…

Gemology Book Reviews: Careers

Artists, lapidaries, and gem merchants all have stories to tell. Three very different books with varied perspectives explore the lives of people…

Rubellite Tourmaline Buying Guide

Like all tourmaline gemstones, rubellite wears well in almost any type of jewelry. This stone’s raspberry-like color draws a great deal of attention.…

Jewelers’ Pricing Survey

The International Gem Society (IGS) ran a jewelers’ pricing survey in 2002 and 2012. Over those ten years, we saw significant changes in the world’s…

Jewelry Nomenclature: Gem Earrings

Earrings are available in many styles. Learn to identify the most popular types of metal and gem earrings and the parts that comprise these jewelry…

Jewelry Nomenclature: Gem Rings

Though rings may come in many styles, gem cutters will regularly encounter a few common types of gem rings. Learn how to identify these popular designs.…

Spinel Buying Guide

Our spinel buying guide can help you learn how spinels are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.…

Topaz Buying Guide

Our topaz buying guide can help you learn how topazes are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.…

Ruby Buying Guide

Our ruby buying guide can help you learn how rubies are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.

How To Make A Rock Lamp

With the right tools and a little drilling know-how, you can create a rock lamp with an agate or jasper base, an oil lamp, and a glass lantern.

Can Diamonds Burn?

Diamonds may form under intense heat and pressure, but under certain conditions, diamonds burn.  Learn the science behind a diamond’s fiery…

Do Natural Rubies Fluoresce?

Both natural and synthetic rubies fluoresce under UV light. Learn how slight differences in fluorescence patterns can help gemologists distinguish…

Are Serengeti Rubies Real Rubies?

Although Tanzania is a source of rubies, so-called Serengeti rubies are more likely to be garnets. Learn more about rubies and misleading gem names…

Gemstone Orientation For Beginners

Choosing the best gemstone orientation for your rough takes skill and experience. Learn what factors you should take into account before cutting.…

Is Uranium Glass Safe To Facet?

Uranium glass, or Vaseline glass, is a prized collector’s item and is generally safe to handle. But is it safe to facet? Learn about the potential…

Gold Refining Advice For Jewelers

Before you turn the alloyed gold you got a great deal on into gold jewelry, carefully consider what gold refining system will work best for you.

What Causes Emerald Fractures?

Emeralds get their green color from chromium and vanadium. Learn how the presence of these elements affects their formation and causes emerald…

Faceting Tips For Exotic Gemstones

Some gems are seldom faceted because they’re rarely found in nature or rarely used for jewelry. Learn a few tricks for faceting seven exotic gemstones.…

What Is A Chameleon Diamond?

A classic chameleon diamond can change color from green to yellow under certain conditions. Learn more about this process and other color change…

How To Dry Opals Safely

Opals should be handled with care. If you buy opals that have been kept in water, follow these instructions to dry them safely.

Facet Designs For Beginners

What are the best facet designs for novice gem cutters? Find recommendations for cutting styles, books, resources, and gemstone rough here.

Why Choose a Barion Cut?

Gem faceters must consider factors like brilliance, color, and faceting yield before choosing a cut style. Learn what a Barion cut can bring to…

Sphalerite Appraisal

Learn what factors most influence a sphalerite appraisal and what kind of jewelry will best showcase this beautiful gemstone.

Opal Jewelry Tips

Opal jewelry is lovely, but aren’t these gems prone to scratching and breaking? Learn the best ways to wear these colorful but delicate stones.…

What Is A Reflectometer?

What’s the difference between a reflectometer and a refractometer? If you’re interested in studying or buying gems, learn the facts here.…

Make a Bracelet

A step by step procedure on how to make a bracelet. Detailed information on tools and materials needed. Read and Understand instructions to complete…

Spectroscope Instructions

The spectroscope is one of gemology’s principal tools. Our basic spectroscope instructions will teach you how to operate and calibrate this…

Tremolite

Tremolite runs in a solid-state series with actinolite to ferroactinolite. (Ferroactinolite is not used as a gemstone.) Details and information…

Vivianite

Vivianite is fragile and soft that cut gems would be difficult to handle safely,let alone wear.The color is very rich, and a few stones have been…

Spinel

Spinel has played an important part in gem history. Prior to the last century, it was impossible to distinguish from ruby and sapphire once it was…

Rhodonite

Rhodonite is a popular and useful decorative material, ranging in color from pink to a fine rose-red.This article covers informative content…

Gem Price Guide

A guide for the price of various gemstones that is based on various sources for commonly traded goods. However, gems are sold outside this range…

Interviews

The transcription of the interview of International Gem Society IGS with C.D. Parsons of Santa Paula, Calif. and Gerald Wykoff GG, CSM.

EPIDOTE

The epidote group consists of 3 related minerals that are well known to collectors and hobbyists, plus 1 popular gem mineral and 3 less common species.…

Gem Designs

This is a Gem Design Index. A list of several gem designs with details and instructions. Gather more information on various designs that are available.…

Diamonds

Diamond are our most popular gem. ts history of use and great value extends thousands of years into the past. Find out more on the properties of a diamond.…

Tucson 2002

This year we asked our members for their impressions of the Tucson show. Here are their impressions. A little insight on the Tucson 2002 extravaganza.…

The Wire Artist Jeweller

This is a neat, simple, project that will teach you how to string beads with wire. You can take these skills and create bracelets, necklaces, earrings,…

A Tribute to Bench Jewelers

A Bench Jeweler are artisans who sit in the back room patiently working on and carving Jewelry with very little to no acknowledgement on their work…

Birthstone Chart

Birthstones listed by month. Also listed are both the Modern Birthstones and the Ancient Birthstones.

LAP MATERIALS

A tabel of Lap Materials, Compliments of The International Gem Society. These figures are approximate and are put together for your general reference.…

Ring Size Comparison Chart

Ring Size Comparison Chart compliments of the International Gem Society. A conversion table of Ring sizes. 7 different ring size equivalents…

Gem Structure Chart

A gem structure chart that shows various information on a specific structure and gems of example. Details include Refractive Indexes, Pleochroism…

METAL/WAX FORMULAS

Jewelers need to know how to determine how much gold is needed for a wax mold. Here are three methods for you.Information and tips on metal or wax formulas.…

BOOK REVIEW, Gem Dealers Secrets

A book review on “Gem Dealers Secrets”. It is always a treat to find a book that lives up to expectations and is entertaining to read. This is such a…