International Gem Society

Crystallography is the study of crystalline solids and their properties. Learn how mineralogists use this to identify minerals.

As a December birthstone, blue zircon is very popular. But are blue zircons natural? Learn how zircons form and get...

How do scientists define a mineral? Learn what minerals are made of, the difference between gemstones and minerals, and their...

Natural radiation can create beautiful colors in many gems. Learn how natural radiation works and what gems are most commonly...

Are zircons natural gemstones? Learn how zircon heat treatment works and the difference between zircon and cubic zirconia.

Watch lapidarist Jim Buday facet a step-cut Montana sapphire design. This version of the traditional cut produces a very bright...

Is zircon the oldest mineral? Find out why zircon is important for scientifically dating rocks and how to learn a...

There are key differences between gemology and mineralogy. Learn about these disciplines and how studying mineralogy can benefit gemologists.

https://vimeo.com/891998005?share=copy Check out the full-length video on the International Gem Society YouTube Channel. Jim Buday takes you step by step through...

https://vimeo.com/848434700?share=copy Check out the full-length video on the International Gem Society YouTube Channel. About Jim Buday Jim Buday was born and...

https://vimeo.com/839864900?share=copy Check out the full-length video on the International Gem Society YouTube Channel. About Jim Buday Born and raised in...

What do gemologists need to know when appraising turquoise? Learn what are the main value factors to consider and the...

Almost all turquoises receive enhancements for jewelry use. Learn how to identify the most common turquoise treatments and synthetic options....

People have prized turquoise jewelry for millennia. Learn about these traditional turquoise designs that still influence modern artisans.

https://vimeo.com/video/861664423 Check out the full-length video on the International Gem Society YouTube Channel. About Jim Buday Born and raised in...

Is all turquoise turquoise color? Learn about this gem's most popular natural colors and how people have prized them for...

Beautiful turquoises tend to show wear over time. Our turquoise care guide will show you the best ways to clean...

Turquoise gems can show many beautiful variations. Learn how turquoises form and how geology affects their color, shape, and durability....

Some black gemstones are so well-known their names have become synonymous with the color black. Others are less well-known by...

For centuries, balas rubies were prized by royalty. Learn what happened after gemologists identified these gems as red spinels instead....

Although the world’s most famous spinels are named “rubies,” these gems are distinct species. Learn the stories behind four of...

Available in many colors, spinels are becoming more popular with consumers. Learn how spinels form and how these gemstones get...

The materials trapped inside gems hold a wealth of information. Learn what the most common types of spinel inclusions reveal...

Learn how gemologists identify cobalt spinels and what qualities you should look for when buying these beautiful, vivid blue gemstones....

Our spinel engagement ring stone guide can help you learn about this beautiful, colorful, durable, but little-known gemstone.

Spinels are rarely treated, but gemologists should know how to detect spinel treatments. Learn about filling, heating, and diffusion.

The anniversary gift for year 1 is gold, and the anniversary gift for year 2 is garnet. Our chart tells...

You might find synthetic jade for sale, but is this material really lab-made jade or something else? Learn how to...

Our table comparing the properties of jade lookalikes with natural jade will help gemologists distinguish authentic jade from simulants.

How does the Uyghur Forced Labor Prevention Act of 2021 affect imports of Xinjiang nephrite jade from China? Learn what...

Jade color trade names describe prized hues and patterns in jadeite and nephrite stones. Learn about the most popular and...

What do the 2021 Myanmar sanctions cover and will they affect the jade trade? Learn about the origins, scope, and...

Nephrite is one of the two distinct minerals commonly known as jade. While nephrite doesn't match the variety or the...

Jade is an elegant choice for an engagement ring stone. Our jade engagement ring guide will show you how to...

Learn everything you need to know about maw sit sit, a rare, vibrant green gem rock used to make beautiful...

Jadeite and nephrite occur all over the world. Learn about the most notable and productive gem-quality jade sources..

Nephrite jade carvings can teach us about Ancient China. See how ideas of transformation are reflected in numerous ritual objects....

Jade toughness is legendary. However, this gem isn’t indestructible. Learn what makes jadeite and nephrite so tough and how to...

The minerals known as jade, jadeite and nephrite, appear similar but have different properties. Learn how these materials form geologically....

With beautiful green to blue-green colors and interesting patterns, variscite is a popular hobbyist material for cabochons.

Should you wear chrysoprase jewelry only at night to protect the gem’s striking green color? Learn the facts here.

Too soft for jewelry use, legrandite is a popular collector’s mineral because of its intense yellow color and aesthetic crystal...

Beautiful blue colors and the star stone effect have influenced sapphire symbolism through the ages. Learn more about the legends...

Smithsonite occurs across the globe, but facetable crystals are extremely rare. These gems can show a wide range range of...

Vivianite is so fragile and soft, any faceted gems would be difficult to handle safely, let alone wear. Nevertheless, its...

Did you know most gem species can be distinguished without the element of color? Learn the role gemstone colors play...

Although lapidaries can cut cabochons and decorative objects from massive or translucent eudialyte crystals, transparent material suitable for faceting is...

How does faceting affect gem value? Unique custom-cut gemstones command high prices. Learn how custom cutting compares to factory cutting....

For millennia, artisans have carved intricate cameos from black-and-white onyx. Solid black onyxes, faceted or cabbed, are also popular jewelry...

Our peridot buying guide can help you learn how these gems are graded, what to avoid, and how to identify...

Learn how lab grown sapphires are made and how gemologists can distinguish natural from synthetic sapphires.

Although covellite has attractive blue colors and shows iridescence, this rare mineral is difficult to cut. You can scratch it...

Our sphalerite buying guide can help you learn how these gems are graded, what to avoid, and how to identify...

Although bytownite occurs throughout the world, this feldspar variety is rarely encountered in gem-quality condition.

A little-known and rare collector’s gemstone, villiaumite is very difficult to facet. Its toxicity also makes it inadvisable to handle...

A glossary of frequently encountered gemstone faceting terms for the student gemologist. Our list covers gemology, gem cutting, and equipment....

Faceting wax or dop wax comes in different colors with different melting points. Learn how to choose the wax best...

What is the birthstone for September? The birthstone for September is sapphire. Sapphires are members of the gem species corundum....

Emerald crystals can grow very large. Learn about some of the world’s largest emeralds, whether rough, faceted, or carved.

Heliodor is a member of the beryl family. This stone is known for its range of yellow colors — from...

Fantasy gem designs combine elements from faceted and cabbed stones as well as artistic embellishments. Learn the basics of this...

Emeralds from different sources can vary in quality. Learn how to identify emerald origins by analyzing the optical and physical...

Proustite crystals have magnificent red colors and good brilliance. Although facetable, they're too soft for jewelry use but highly desired...

What does it take to facet gems? Patience and HAI, locking the gem at the right height, angle, and index...

Although aesthetically magnificent wulfenite crystals are often too thin, soft, and sensitive to cut for jewelry, rare faceted pieces are...

Before you turn the alloyed gold you got a great deal on into gold jewelry, carefully consider what gold refining...

Most black diamonds used in jewelry are enhanced, but natural black-colored diamonds do exist. Learn more about these as well...

Though perhaps best known as inclusions within other gems, rutile crystals themselves can be faceted or cabbed as curiosities for...

Xonotlite is strong and can take a good polish. However, these gems are extremely rare, both as a species and...

Jewelry making is a great way to tap into your creative side. Learn what jewelry making tools you’ll need to...

Although abundant in various lava rocks, leucite is extremely rare in gem-quality form and often has a milky or cloudy...

We live in a world of crystals. Learn what they are and where you can find them, from deep underground...

A ceramic lap is an excellent choice for polishing gemstones. Here is a guide for properly charging ceramic laps and...

Small, cuttable crystals of very rare zektzerite are found only in a mountainous location in Washington state. Faceted pieces would...

Gem-quality, colorless, facetable petalite is rare and desirable to collectors. More so if the stones are large and free of...

Polishing synthetic corundum without leaving pits requires certain techniques and tools. Get expert lapidary advice here.

Ranging in color from pink to a fine rose red, rhodonite is a popular material for jewelry and decorative objects....

Polishing gemstones is difficult to master. Pre-polishing plays a major role in how well a gem can take a polish....

Visit one of the top gem hunting spots in the US. Go alone or with the family. A gemology-themed vacation...

Although not suitable for jewelry, apophyllite is a popular collector's piece. Perhaps the whitest of all gems, some cut specimens...

Gem formation usually involves mineral crystallization and other geological processes. Learn how these affect the gemstone properties gemologists study.

One of the rarest of all facetable gems, cut cuprites can show magnificent deep red color. However, these beautiful stones...

Learn how gemstone optical properties, like refractive index and pleochroism, help gemologists identify gems and lapidaries choose cuts.

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

Rare and difficult to cut, anhydrite is seldom faceted. However, this material can be carved into beautiful objects. “Angelite,” a...

More well-known as rare inclusions in emeralds, parisite crystals are usually small and seldom faceted.

Our spinel buying guide can help you learn how spinels are graded and how to identify a high-quality stone or...

Commentaries on the foundation stones of the Book of Revelation influenced the development of the Western birthstone system. Learn more...

Golden beryl, also known as heliodor, can display rich colors and is an excellent gem choice for jewelry. Learn more...

Finding good diamond rough and the right equipment can be challenging for a non-professional diamond cutter. Learn what to look...

Independent report by International Gem Society on the Best Engagement Ring Insurance on the Market in 2022.

Although hard enough to be worn safely in jewelry, euclase in beautiful colors is rare over a few carats. It’s...

There are few guides to gemstone wholesale prices. However, appraising gemstones requires in-depth knowledge and experience, not just price lists....

Looking for alternatives to a classic diamond engagement ring? Learn about your options and see some wonderful photos of colored...

Jewelry attachments are the pieces used to hold jewelry items together. Learn about the most popular types as well as...

Garnet symbolism is rich and varied. The January birthstone has inspired many legends and popular associations with love, friendship, light,...

Rare phenakite is a very hard gem material suitable for jewelry. Usually colorless, cut stones have little fire but can...

Earrings are available in many styles. Learn to identify the most popular types of metal and gem earrings and the...

In Exodus, the breastplate of Aaron was said to hold 12 gems. However, the gemological identities of the stones, like...

Bracelets and necklaces share much of their terminology. Learn the names and functions of the different parts of these popular...

These cleaning tips will make polishing silver jewelry a little easier. Learn how to prevent tarnish and how to clean...

Gem collectors prize tugtupite, the "Reindeer Stone," for its rich colors and intense reaction to ultraviolet light. Sporadically used in...

Though rings may come in many styles, gem cutters will regularly encounter a few common types of gem rings. Learn...

An inexpensive pocket spectroscope can be great for student gemologists as well as pros who need to identify gems while...

To date, only one locality — Mont St. Hilaire, Quebec, Canada — has produced facetable serandite. These extremely rare gems...

Want to start cutting beautiful star gemstones? Here are some helpful gemological resources for novice lapidaries and jewelers.

If you want to buy a diamond online rather than at a brick-and-mortar store, you’ll need to be well-informed. These...

Clinohumites and chondrodites can make beautiful gemstones with rich colors, but these members of the humite mineral group are rare...

Although emeralds and peridots are both green gems, differences in shade might make it hard to pair them in jewelry....

Fancy cut diamonds can have any finished shape, except round. These stones have their own grading criteria, in particular regarding...

Truly a collector’s gem, weloganite is very rare and seldom cut. This stone can show pale yellow colors.

Silk inclusions in sapphires are hard to detect. Learn to pick the best orientation and cut for these gems. You...

Colemanite is an abundant mineral, and transparent material isn’t rare. However, gem cutters rarely facet these typically pale stones. Difficult...

Online diamond sellers have occasional sales throughout the year but it's time-consuming to keep track of them all. One thing...

Here are the top 5 facts about diamonds you need to know: (1) the supply of blood diamonds has decreased;...

Although transparent dolomite crystals are fairly abundant and popular collector’s items, faceted gems are soft, fragile, and rarely seen in...

Throw the old engagement ring budget rule in the trash. You should spend as much or as little as you...

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

Typically colorless with a “sleepy” look, cryolite is rarely found in nature. Rough suitable for gem faceting is extremely scarce....

Cobaltite cabochons can have a lovely metallic luster. However, this gem material is very seldom faceted.

A gemstone's optic sign may be listed as either + or -. Learn whether impurities in a specific stone or...

Chambersite is an exceedingly rare mineral. Although it has properties suitable for jewelry use, its crystals occur in very small...

Are opals too delicate for jewelry? Learn how to choose the right settings for opal wearability, so you can enjoy...

Massive white barite (also called known as baryte) looks like marble and could be used for decorative purposes. In spite...

The rarest plagioclase feldspar, anorthite is very rarely faceted.

What are the best techniques and tools for polishing girdles? Learn how to complete your faceted gems quickly and easily...

Polished and sliced datolite nodules can show off very attractive colors. Datolite is a popular collector’s mineral, but faceted and...

The GIA grading system describes gem color in terms of hue, tone, and saturation. Learn what the abbreviations and numbers...

Beautiful rose red to pink rhodochrosite crystals are popular with mineral collectors. Although very soft, opaque stones have been fashioned...

Crystallography is the study of crystalline solids. Learn the most common terms gemologists use to describe the structure of crystal...

With lovely colors and intense pleochroism, faceted scorodite is a prize for collectors of the rare and unusual. However, it’s...

Although anglesites with pale colors can show great dispersion and brightness, they’re difficult to cut and inadvisable to wear. Faceted...

Platinum and gold are the two of the best types of metal for an engagement ring. But they aren't the...

Kyanite’s physical properties make it very difficult to facet. However, it’s a popular collector’s gem, especially in sapphire-blue colors.

A green to blue-green variety of microcline, amazonite makes a wonderful gemstone for cabbing and carving.

Learn how to modify a powder scale for specific gravity testing. A handmade wire basket will make this easy-to-use scale...

Siderite is difficult to cut, but this light brown collector's gem has yielded faceted pieces of great beauty.

Learn how to organize your gemstone collection. Choose the storage and display options that are right for you and create...

The gem material known as serpentine actually encompasses several related mineral species. For millennia, people have cut serpentines into beautiful...

Anatase occurs in many beautiful colors, such as deep indigo and amber yellow. However, these rare gems are seldom transparent...

Purpurite is too soft for jewelry wear and never transparent. Nevertheless, lapidaries have cut cabochons from this material with magnificent...

Learn which rough gemstones are ideal for beginning faceting practice. A progression of relatively inexpensive gem species can teach important...

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

Probably fewer than a dozen creedite gems have ever been faceted. This rare mineral is rarer still as a cuttable...

Our jewelry insurance guide reviews the policies of the top eight companies. Learn what to look for so you can...

Ludlamite has a lovely green color, but cut stones are extremely rare. Large crystals of this phosphate mineral are known...

Both jadeite and nephrite have inspired beautiful works of art and a rich body of lore. Jade symbolism covers themes...

Will your gem fit in a standard setting? Use this chart of standard gem sizes for popular cuts and also...

Prosopite is usually a nondescript mineral with no gem significance. However, beautiful blue specimens are sometimes cut for jewelry.

Hematite has a long history of use as a pigment. As a gemstone, this material is often carved but very...

Wavellite is a very attractive mineral, well-known to collectors. Its radial aggregate crystal clusters can be cut into extremely interesting...

Rare stibiotantalite possesses an interesting mix of physical and optical properties that help distinguish it from other earth-toned gemstones. However,...

Updated July 23, 2022. Up-to-date promo codes, coupons, and sales to save you money on diamond rings, engagement rings, jewelry,...

Opals are unique gems with their own unique terminology. Learn the modern standard system for classifying and appraising opals used...

Typically blue, durable, and easy to cut, sodalite is highly desired by hobbyists. Even stones that lack transparency make lovely...

Even the most general definition of a gem has many exceptions. Learn what qualities have been used to identify gemstones...

Mellite is a rare and unusual organic gemstone. Although soft and fragile, the “honey stone” is quite beautiful when cut....

Do you have an offer for bargain rubies that's too good to be true? Learn what you need to know...

Since ancient times, people have believed gems could have healing properties. Let’s take a look at some popular gemstones with...

Although too fragile for most jewelry use, fluorites are often faceted for collectors. They occur in a wide range of...

A rather rare mineral, lovely blue-green grandidierite is seldom seen in gem or jewelry collections. Translucent material is sometimes cut...

Will wearing gems that touch the skin of your finger bring you health benefits? Before you buy any ring stone,...

Asscher diamonds get their name from the Royal Asscher Diamond Company, the Dutch company that invented the cut. It features...

Round cut diamonds have been around for centuries. As a timeless diamond cut, they offer exceptional resilience in popularity when...

Cushion-cut diamonds are the second most sought-after diamonds on the market today. The cut's popularity comes from combining two other...

How can you get lower gem and jewelry insurance quotes? Asking a potential insurer these four questions could help lower...

Natural alexandrite is popular and rare, which creates a market for synthetics. But is lab-created alexandrite real alexandrite? Learn the...

Before you buy jewelry and gemstone insurance, learn what to ask insurance companies and make sure the policy meets your...

Also known as heliotrope, bloodstone is the traditional March birthstone. This dark green, opaque chalcedony with red to orange spots...

Your homeowners insurance may cover gems and jewelry, but don’t assume it covers all risks or the value of your...

Uranium glass, or Vaseline glass, is a prized collector's item and is generally safe to handle. But is it safe...

Oval diamonds are consistently one of the most popular diamond cuts on the market. Oval diamond engagement rings are popular...

A beautiful but rare mineral, kämmererite is extraordinarily difficult to facet. As a result, the availability of cut gems is...

Need insurance for your jewelry? You’ll need jewelry and gemstone appraisals. Learn what info they should include and who to...

With study, care, and the right tools, hobbyist gem cutters can add diamond cutting to their repertoire. Get started with...

Historically a popular black gem, jet has declined in popularity in modern times. Although jet jewelry has been long associated...

Can gemstone pricing formulas help gem merchants and buyers make fair deals? Learn what factors should play a role in...

For faceting, the distinction between gems and minerals is usually clarity. However, learn why the decision to cut may be...

Aquamarines are evaluated based on the Four Cs: color, clarity, cut, and carat. Learn how each factor affects aquamarine grading...

The IGS Gem Price Guide covers commonly traded colored gemstones as well as more unusual, collectible gems. The values listed...

An attractive but uncommon mineral, spurrite has seldom been cut as a gemstone. However, it has the hardness and tenacity...

Kurnakovite is difficult to cut, inadvisable to wear, and usually colorless. Consequently, faceted specimens are extremely rare.

Rhodizite is tough enough to make an excellent jewelry stone. However, it's quite a rare mineral. Faceted specimens are extremely...

Learn what gemstone dispersion means, what causes it, and how it relates to other optical effects.

Bench jewelers work very hard with little or no acknowledgement, creating and repairing treasured possessions. These stories pay tribute to...

The epidote mineral supergroup contains many related species of interest to collectors. However, epidote itself is the one most likely...

Deep-cut gems like Barions may not fit in standard ring mountings. Jewelers can try to find special mounts or custom...

Obsidian is the most common form of natural glass and occurs in many attractive varieties. Since prehistoric times, people have...

Phenomenal gems seem to do magical things with light. Learn the science behind optical effects like cat’s eyes and star...

Colorless pollucites lack fire when cut and are usually small. However, this very rare cesium mineral is a coveted collector's...

The most common aquamarine enhancements try to turn blueish green stones pure blue. Learn how heating and other aquamarine treatments...

Aquamarines are fairly tough jewelry stones, but they do have some weaknesses. Learn about aquamarine durability and what precautions you...

Synthetic aquamarines are relatively rare, but gemologists may encounter them. Learn how these stones are made and how to distinguish...

Aquamarines can look great, but what’s the best way to mount them? Novice jewelers should learn the pros and cons...

How can gemologists quickly distinguish aquamarines from aquamarine imitations? We’ll review some common lookalikes and their most notable differences.

Rare phosgenite typically shows pale colors. This material is difficult to cut and too soft for jewelry wear. However, its...

Aquamarines are popular gemstones and can be found in many areas worldwide. Learn about some prized varieties and the most...

As beautiful as a diamond, a faceted cerussite actually has higher dispersion and usually excellent transparency, colorless or light body...

The March birthstone, aquamarine is a popular gem. Learn how aquamarines form, what they look like, and how they get...

Very rare milarite crystals can occur in green and yellow colors. Transparent material can yield small but pleasant looking faceted...

Aquamarines have been cut into many large and beautiful gemstones. Let’s take a look at six of the world’s most...

Transparent, gem-quality magnesite is rare and beautiful, with colors ranging from colorless, white, and gray to a yellowish brown.

Amber has a long history of ornamental use and popular associations with animals, energy, and the Sun. Learn more about...

Faceted eosphorites in pale colors are quite attractive and easy to cut. However, these very rare gems are too soft...

Sapphirines are durable but very rare gemstones. Although named after their typically sapphire-blue color, these gems can occur in different...

Many factors contribute to gemstone brightness. Learn the role a gem's refractive index plays and the difference between gemology theory...

Lazulite makes a magnificent, deep blue gemstone. Although the mineral itself occurs widely, gem-quality rough is limited. Specimens are prized...

Identifying diamonds requires the right equipment. Learn what diamond grading tools novice professionals or hobbyists need.

Although adamite occurs in many localities, it's very rarely cut as a gem. This mineral is much too soft and...

Staurolite crystals in opaque cross shapes are popular gemstones. However, this material is very rarely transparent or facetable. These dark...

Amblygonite gems are usually pale straw yellow. Although they are too soft and cleavable to make good ring stones, collectors...

Soft, fragile, and hard to cut, celestite or celestine is seldom seen in gem collections. These gems are usually colorless...

Some gems are seldom faceted because they're rarely found in nature or rarely used for jewelry. Learn a few tricks...

Our rubellite buying guide can help you learn how rubellites are graded, what to avoid, and how to identify a...

Discovered in 1989, paraíba tourmalines are among the world’s most prized gemstones. These rare gems are renowned for showing intense...

Rare chrome tourmaline can show an emerald-like green color. With a highly desired color and tourmaline's excellent qualities as a...

Cutting tourmaline can be difficult. Learn how to cut tourmaline, including faceting techniques to minimize the risk of damaging your...

Looking for a tourmaline jewelry stone? If you like green and you're on a budget, green tourmaline or verdelite is...

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

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

The Usambara effect is a gemstone color change phenomenon distinct from pleochroism or the alexandrite effect. Tourmaline and other species...

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

Diamonds may form under intense heat and pressure, but under what conditions can diamonds burn? Learn the science behind a...

Fuzzy refractometer readings may be the result of poorly faceted gems, the wrong amount of refraction liquid, and even stone...

Although you can't weigh a gemstone in a jewelry setting, you can get a close approximation of the gem weight...

Learn how gems absorb wavelengths of light and how gemologists use gemstone absorption spectra to identify gems. There’s more to...

The glass used to make refractometer hemicylinders is susceptible to tarnish. Here's a step-by-step guide for re-polishing a refractometer hemicylinder....

One-carat oval diamonds are versatile alternatives to one-carat rounds. Our guide can help you find the right oval-cut diamond for...

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

Using heavy liquids to measure a gemstone's specific gravity poses some health hazards. Learn the techniques and precautions that gemologists...

You can use an electronic scale for calculating specific gravity if you have the right accessory, a hanging basket for...

Using a balance scale to test specific gravity is a recommended practice in gemology. Learn to make your own scale...

The optical properties of gems attract our eyes and can give a cut stone a unique character. However, gemstone physical...

Learn specific gravity testing methods for gem identification. Our 5-part introductory series starts with the basics and key definitions.

Corundum gems receive more types of treatments than any other stones. Learn how to test rubies and sapphires for signs...

Any stone that changes color under different types of light is a rare treat for collectors. Color change garnets show...

The AGTA has proposed the use of gemstone treatment codes to promote disclosure and a common language for these procedures....

Vapor deposition can be used to enhance gemstones like topaz and quartz with a metal coating or sheen. Learn how...

Our topaz buying guide can help you learn how topazes are graded, what to avoid, and how to identify a...

Pyrope always occurs in series with other garnet species. Common, dark red garnets are a mixture of almandine and pyrope....

Gemstone enhancements improve the appearance and wearability of gems. Learn about the most commonly used procedures and frequently treated types...

Gemologists may immerse gems in refraction fluids during examinations. This refractive index list of household liquids offers some common alternatives....

Novice and expert gemologists discuss their experiences at the celebrated annual February Tucson Gem and Mineral Show. You'll find reviews...

A little gemology goes a long way. Learn how to clean your gemstone jewelry safely and how to deal with...

Properly pricing faceted gems can be a daunting task for investors. Learn how to research gem prices and calculate your...

Behind every mystical gem is a merchant. Since ancient times, malachite has been “the salesman's stone.” Learn more about malachite...

Accurate descriptions and quality photographs are essential for marketing your gems online. Learn about options and best practices for improving...

Determining where to sell your gems — whether online or in-person — can be difficult. Here’s a look at the...

How do you say “love me” with a stone? Learn about lapis lazuli symbolism and legends. This beautiful blue mineral...

What negotiating strategies work best in the gem trade? Learn how some general principles and a win-win mindset can help...

Research is crucial for success in any business deal. To prepare for gemstone negotiations, focus on these three subjects to...

Many people consider beautiful sky blue turquoise stones to be lucky. Learn about the turquoise symbolism and lore of Native...

Your gem investment profits depend mostly on the prices you set through negotiations. Understanding four key business principles will help...

How should you pay for investment gems? Learn the pros of cons of three options for financing gem investments —...

To make a profit investing in gems, you’ll need a network of gem trade contacts. Here’s some advice on how...

Investors have many gemstone sourcing options, but which ones will work best for you? Learn the pros and cons, as...

Lab-grown stones have the potential to disrupt the gem market. Learn how they can affect supply and demand and whether...

Topaz's most popular mystical association has been with wealth. However, topaz symbolism and lore also covers areas such as health,...

Gemstone pricing can vary greatly between dealers. Learn about the myriad factors that go into prices for both colored gems...

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

Most gemstones are rare, but some are rarer than others. Learn how gemstone rarity and ease of replacement can affect...

Inclusion management is one of the most challenging aspects of gemstone faceting. Learn when to remove and when to keep...

The gem market can be very subjective. Nevertheless, investors can make money by starting with the basics: understanding supply and...

A gemstone’s clarity grade indicates how free it is of inclusions and blemishes. Learn how to decipher the GIA clarity...

Good-quality gemstones are expensive, but you can make money investing in gems even if you have a small investment budget....

How long should investors hold on to gemstones? Learn how your investment goals, business model, and patience affect your investment...

Gemstone investors must keep up with global trends when evaluating market risk. Learn how studying sociocultural factors can lead to...

You can’t eliminate all risks from gem investing, but understanding the risks you’ll face and your appetite for them will...

Successful investing in gemstones requires knowledge and experience. The IGS Buying Gems for Profit course will give you the knowledge...

Gem pricing isn't easy, and guidelines aren't always fixed. Learn what factors gem cutters should consider to determine a fair...

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

Oil treatment is a standard industry practice for enhancing emeralds. However, the treatments are not permanent. Learn how to re-oil...

Meteorites can make beautiful, unique jewelry. This primer on meteorite terminology will help you buy the perfect meteorite jewelry piece...

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

Emerald fillers can improve the beauty of these gems but also have some drawbacks. Learn how to choose the right...

Our ruby buying guide can help you learn how rubies are graded, what to avoid, and how to identify a...

Aquamarine is the blue to blue-green variety of beryl. If you encounter so-called white aquamarines, buyer beware. Learn the facts...

Trapiche emerald gems are some of the world's rarest emeralds. Learn where they're found and how their characteristic “spoked wheel”...

What's the difference between a lab-created emerald and a natural emerald? Is a synthetic gem a real gem? Learn the...

Curved striae or lines are a telltale sign of synthetic ruby and sapphire. If you're having trouble seeing them, here...

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

There are many ways to grow ruby and sapphire in a lab. However, determining the best synthetic corundum for faceting...

Emerald symbolism encompasses not only royalty but also wit, eloquence, and foresight. Learn more about the legends surrounding this prized...

The best rough sapphire stones may come from different sources, depending on the color you want. However, valuable blues may...

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

Ruby and sapphire origins greatly affect the values of these prized gems. Learn where these stones occur and how inclusions...

Many cultures have long considered ruby a king's gem. Not surprisingly, ruby symbolism and lore have many associations with power,...

How do gemologists distinguish between rubies and pink sapphires? Learn about the chemistry of corundum and the history of the...

Transparent mimetite crystals are extremely rare, and very few have ever been faceted. Cabochons with rich orange and yellow colors...

Several species of marine mollusks produce stony growths called calcareous concretions or non-nacreous pearls. Varieties such as conch pearls, tridacna...

What’s the average gemstone faceting yield from a single piece of rough? Learn how to estimate how much material you’ll...

Not all pearls are perfectly round and white. Learn about keshi pearls and soufflé pearls, which can form as cultured...

Fibrous pectolite has long been a curiosity for gem collectors. Compact material can make wonderful cabochons, and transparent crystals are...

You'll find gem cutting acronyms like L/W in faceting guides. Learn what these frequently used terms mean and how they...

Väyrynenite is a very rare mineral. Crystals as well as faceted gemstones in reddish, pinkish, and orange colors are prized...

Deep red pyrargyrite occurs in a number of localities in well-formed but small crystals. However, facetable rough is rare and...

Dioptase has a beautiful, emerald-like green color. Although this mineral isn’t rare, gems are seldom faceted because of a paucity...

Made from two or more materials, assembled gems can make durable and affordable jewelry. Learn more about gemstone doublets, triplets,...

Ranging in color from pale yellow to brown, reddish, and green, microlite cabochons are prized by collectors. Faceted gems are...

One of the major mineral constituents of lapis lazuli, haüyne is rarely found and faceted as a distinct gemstone. Collectors...

This table contains a selection of minerals gemologists may encounter as jewelry stones or gem specimens. The gems are sorted...

Measuring specific gravity helps gemologists identify gemstones. The following table lists the specific gravity values for a variety of gem...

A relative newcomer to the world of gemstones, ekanite is rare and usually quite radioactive. When cabbed, some ekanites can...

Difficult to facet and typically colorless, beryllonite is a rare collector’s gem. Some specimens can show a striking cat’s eye....

Friedelite is not abundant, and gem-quality material is rarely seen even in large collections. Faceted gems are true collector's items....

Collectors prize deep blue azurite crystals, but faceted gems are extremely rare. However, azurite frequently occurs mixed with green malachite,...

Seldom seen even in mineral collections, whewellite is very rarely faceted. It’s mostly desired as a curiosity because of its...

Jeremejevite would make a durable and attractive jewelry stone, but this rare mineral occurs even more rarely as facetable material....

How do you make money investing in gems? What should you buy, for how much, and how can you add...

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

While the colors of spessartite garnet gemstones cover a wide range of orange shades, the mandarin garnet is as pure...

Gemstone transparency describes how much light passes through a gem and how it scatters. Learn what causes a gem to...

Refractive indices and double refraction (birefringence) help gemologists identify gems. The following table lists these values for selected gemstones.

Gypsum is one of the most abundant minerals, but gem-quality crystals are very rare. This material is extremely difficult to...

Bright, silvery metallic cabochons of algodonite and domeykite are attractive and unusual. Faceted pieces are rarely seen but very beautiful...

Lovely saffron-colored crocoite is quite a rare mineral. Although too soft and brittle for jewelry wear, a few crystals have...

With protective settings and special care, these seven beautiful but delicate engagement ring stones can help you make a unique...

Do you want to buy a diamond for an engagement ring? Don't. Still want to buy a diamond? OK. Here...

Test your ability to sort diamonds by color with our fun and quick Diamond Color Sorting Quiz. Learn a thing...

Large, faceted scheelites are among the most beautiful of all collector’s gemstones. They occur in many colors and fluoresce very...

Willemite is prized for its intense green fluorescence. Too fragile for jewelry use, faceted specimens are extremely rare.

Brazilianite's lovely green to yellow colors make it a must for gem collectors. Large faceted stones are often flawed, but...

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

Separate fact from fiction and you’ll find lab-created diamonds make great alternatives to mined diamonds. Our guide will show you...

The US Federal Trade Commission (FTC) can help jewelry marketers avoid making deceptive claims. Learn about the FTC diamond jewelry...

Blockchain tech can provide secure, digital transaction records. Can blockchain diamonds resolve ethical and legal issues related to sourcing and...

NGOs and movies have helped raise awareness of conflict diamonds, and governments have taken steps to stop their trade. How...

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

Once the stone of royalty, the fragile opal has a convoluted personality and lore. Opal symbolism is as varied as...

Yugawaralite is a very rare colorless to pinkish zeolite mineral. Little facetable material exists, so a cut yugawaralite would be...

Pyroxmangite grains are rare, seldom clean enough to facet, and difficult to cut. However, when cut, they are extremely beautiful...

Renowned for its delicate blue-green shades, phosphophyllite’s beauty is enhanced by expert cutting. Unfortunately, this gem is quite fragile and...

Gemstone luminescence is a glow that occurs when certain stones are subjected to energy such as UV light. This effect...

For a long time, rare thaumasite crystals — pale, fragile, and with little to no fire — were interesting primarily...

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

Soft and brittle, rare augelites are difficult to cut and unsuitable for wear. Faceted transparent pieces are only found in...

Cassiterite is a durable gemstone with tremendous dispersive fire, especially visible in properly cut pale-colored stones. As the principal ore...

A little-known gem material of truly exquisite color, sky-blue ceruleite takes a very high polish easily and quickly. However, fine,...

Sarcolite is an extremely rare mineral. Tiny, colorless to “fleshy pink” gems have been cut only from material from one...

Although sulfur is very abundant, facetable material is not. Sulfur is also enormously difficult to cut and almost impossible to...

Although many gems show a cat’s eye effect, when the term “cat’s eye” is used alone, it always refers to...

Massive hemimorphite can have a very delicate, blue color. However, it's seldom cut because not very much has appeared on...

A gemstone's birefringence is a measure of its double refraction. Learn how to use it to identify gems and see...

Until 2001, only three painite crystals were known to exist. Since then, additional discoveries have produced many more specimens of...

Cerulean blue papagoite crystals are too small for faceting. However, massive material mixed with quartz can be cabbed, while quartz...

Brucites are extremely difficult to cut. Although too soft for jewelry use, faceted pieces would be great additions to collections...

Brookite usually occurs in very dark colors, transparent only in small fragments. Cuttable crystals are exceedingly rare, making attractive faceted...

Easy to cut but too soft and fragile for jewelry, a faceted witherite would make an unusual addition to a...

One of the most prized ornamental materials in China, chicken-blood stone has been used for centuries to create carvings with...

Amethyst has many popular folkloric associations, from love and spirituality to supernatural protection. Learn more about amethyst symbolism and legends....

Rounds dominate the gem market, but fancy gem cuts offer many beautiful options. Learn about the most popular fancy shapes,...

Not only do gemstone facets create beautiful patterns on gem surfaces, they also help gems shine. While gem cutters will...

Lapidary is the art of working with gemstones. Learn more about the four basic lapidary arts: tumbling, cabbing, faceting, and...

Always a dark, rich green color, uvarovite is one of the rarest members of the garnet family. Usually only seen...

Niccolite’s delicate peachy red color and metallic luster looks beautiful when polished. Gem cutters typically carve this gem material into...

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

Millerite has a rich, attractive yellow color. Massive millerites can sometimes be cut into cabochons but are too soft for...

The IGS survey results for polishing miscellaneous gems include recommendations for popular stones as well as gems seen less frequently...

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

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

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

Cubic zirconia is the most popular diamond simulant currently available. You can find polishing recommendations for this material in our...

Some very popular jewelry stones, such as beryl, quartz, and topaz, fall in the 7-8 hardness range. You can find...

Polishing feldspar, fluorite, apatite, or other gems in the 4-6 hardness range? Our IGS member survey results can recommend some...

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

Although faceting chabazite isn't too difficult, it's too soft for jewelry. However, only a handful of cut chabazites may exist...

The idea of a single birthstone for each month is a modern idea with a long history, but today's consumers...

Learn how varied gemology careers can be. Our gemology book reviews highlight three different approaches — as art, science, and...

The International Gem Society (IGS) ran a jewelers pricing survey in 2002 and 2012. Over those ten years, we saw...

The Mohs hardness scale measures a mineral's resistance to scratching. Find the traditional scale here and a chart of select...

What does it take to become a professional gemologist? Try these sample gemology questions from the International Gem Society certification...

Our step-by-step guide will help you learn to use vacuum casting techniques to create wax models for jewelry.

Our ruby buying guide can help you learn how rubies are graded, what to avoid, and how to identify a...

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

Some opals from Spencer, Idaho show asterism or the “star stone” effect. Learn how to price these beautiful but rare...

Polishing sapphire gemstones can be tough on laps. Learn the pros and cons of different laps and some techniques to...

Flint and mozarkite are types of chert. While flint is known for its practical use, mozarkite is a colorful variety...

What's the best gem cutting machine for novices? Read about some popular models and learn the importance of finding the...

Wax casting makes it possible to create intricate and unique metal pieces for jewelry. Here are some tips for beginners...

Is a flat lap to dop swing really necessary? Learn how a gemstone should contact a faceting machine lap and...

Turkey's gemstones include well-known species such as diaspore, chalcedony, and purple jade, as well as unusual specimens of lesser-known gems....

To pick the right cut for a gem, you need to figure its maximum potential shape. Preforming gemstone rough is...

What's the best doublet glue for creating assembled stone jewelry? Learn about the choices as well as tips for making...

Has your sterling silver money clip lost its spring? If you have experience with metalworking, learn these methods for repairing...

Working with platinum is actually a little easier than working with gold. If you want to add platinum jewelry repair...

A quartz wedge can be used with a polariscope to help a gemologist distinguish the + or – optic sign...

Faceted dark colored gemstones can have intense colors but little brilliance. A simple formula can help a gemologist estimate a...

What factors determine the light return of faceted gemstones? Facet quality, polish, color, and cut style all play roles. Learn...

Cabochon cuts are popular for showcasing opal doublets. Learn a trick for making a bezel setting for doublets that are...

Agate stones typically form slowly in the cavities of ancient hardened lava flows. Learn where you can see this process...

Ring sizing is an important part of jewelry making and repair. Learn a few soldering and annealing tricks from the...

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

Dark green tourmaline and red rubellite gems can look very black in an emerald cut. Learn how to minimize this...

How do you start making a living in the jewelry trade? You need to learn gemology and metalsmithing and get...

Learn how to cut spectrolite and other labradorite gems so you can showcase their striking color flash most effectively.

Learn why citrine gemstones are sometimes misidentified as topaz. A professional appraisal by an independent gem lab is the best...

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

Make gemology for kids educational and fun with these gemstone-themed games for all ages. Try these solo and party activities....

Our gemstone crossword puzzle collection is a fun and challenging way to test your knowledge of gemology, whether you’re an...

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

We make recommendations about the best books to buy and read when getting started in faceting.

Marilyn Monroe said “Diamonds are a girl’s best friend.” Jill St. John said “Diamonds are forever.” Elizabeth Taylor said “Big...

Color change sapphires are those that change color between light sources.

Star sapphire is a type of sapphire that displays asterism, a star-like optical effect.

Padparadscha sapphires show a blend of orange and pink colors, one of the rarest of all sapphire color combinations. Padparadschas...

Quartzite is a rock made up of tightly packed quartz grains. Sometimes, it contains small crystals that reflect light. This...

Smoky quartz comes in every shade of brown, from a light tan to nearly black. This gem is known for...

Microcline is a variety of feldspar. The only microcline you are likely to encounter is amazonite.

A few almandine/pyrope garnets from the US will change with treatment into proteus garnets. In reflected light, they have a...

Hydrogrossular differs from the other garnets in that it is never transparent. It ranges from translucent to opaque. The most...

Jasper is an opaque, solid or patterned variety of cryptocrystalline quartz. All types of jasper take an excellent polish, are...

Marketed as "Gem Silica" this relatively rare, blue to blue-green, opaque to near transparent material is the most expensive type...

Crocidolite, (blue asbestos,) alters to quartz, but while retaining its fibrous structure. This material is frequently stained by iron, giving...

The best-known and generally least expensive variety of chalcedony is carnelian. It ranges in color from yellow-orange to rich, near...

The IGS Gem Price Guide covers many popular as well as unusual, collectible gems. Find your gem’s retail value based...

Synthetic spinel is a widely used jewelry stone. Learn how gemologists can identify lab-made flame-fusion, flux, and Czochralski spinels.

What stones are the trendsetters using to pop the question? Take a look at the diamonds and colored gems in...

Very few vanadinites have ever been cut. This is unfortunate, since their red, orange, and brown colors are rich and...

Idocrase is one of the lesser known and more beautiful collector gems. When properly cut it is as bright and...

Pale pink and brownish red bustamite can make a very attractive faceted gem. However, stones in large sizes are rare...

Cut boleite is strictly for collectors, since it is soft and very rare. Faceted gems of any transparency should be...

Advanced gemological laboratory services and appraisals at cost-effective prices.

A list of False or Misleading Gemstone Names and its Actual Gemological Name. Gathered by the source "Gemstones of the...

Successful tips and guide in identifying Inclusions Found in Natural Gems. Read and learn several ways to identify inclusions found...

This beginner's bead bracelet project is a great way to learn how to string beads with wire. Follow these hints...

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

Ultra Tec Faceting Machine Review . The Ultra Tec has been referred to as the BMW of faceting machines. We...

Vivianite is fragile and soft that cut gems would be difficult to handle safely,let alone wear.The color is very rich,...

Faceting Survey Results for Polishing Sunstone: Get polishing methods for Sunstone. View results for various procedures in polishing Sunstone gemstones....

Faceting Survey Results for Polishing Topaz: Get ideas and methods on polishing Topaz. View results for various procedures in polishing...

Faceting Survey Results for Polishing Tourmaline: Get polishing methods for Tourmaline. View results for various procedures in polishing Tourmaline gems....

Faceting Survey Results for Polishing Garnet stones. Know the preferred polishing methods for Garnet. Also, view results for various procedures...

Polishing Beryls: Get successful tips, suggestions, and methods to polish a Beryl laptype, synthetic emerald laptype, or any gemstone of...

Below are a number of comments, instructions, and hints that I thought would be of interest.  Enjoy:) Tin Lead lap...

Sea shells are one of our most ancient decorations. Our prehistoric ancestors used to string them into necklaces or hang...

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

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

A guide for the price of various gemstones that is based on various sources for commonly traded goods. However, gems...

Glass comes in several natural forms. All are used in jewelry.

Laserblue is a rare, synthetic glass. It's hard for glass but easy to chip.

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

Gahnospinel is a solid-state solution between spinel and gahnite.

Quick facts about the optical and physical properties of diamonds.

Have the information of authoritative gemology books at the click of your mouse. Our gemology interactive media reviews showcase three...

Clinochlore is a family of minerals in the chlorite group. To date, only kämmerite and sheridanite varieties are known to...

No one to date has a total inventory, or a complete database, of gems and all their properties. Gemologists need...

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

Hyperitdiabas is one of the most outstanding minerals I have encountered in recent years. Its appearance striking beautiful and a...

What are the birthstones by month? January is garnet, February is amethyst, March is aquamarine, April is diamond, May is...

Printable chart to convert weights and measures including Carats, Grams, Kilograms, Ounces, Pounds and Troy Ounces Pounds and Pennyweights.

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

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

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

Jewelers need to know how to determine how much gold is needed for a wax mold. Here are three methods...

A book review on "Gem Dealers Secrets". It is always a treat to find a book that lives up to...

Gerald Wykoff has gained worldwide recognition for his "Master's" series of gemological and lapidary books. The first, Beyond the Glitter,...