Discover the vibrant world of peridot gemstones, including their chemical composition, deep-earth origins, mining sources, notable specimens, value & more.
Gemstone identification increasingly depends on high tech instruments such as FTIR, EDXRF and LIBS
Tsavorite is a rare vivid green grossularite garnet, colored by chromium or vanadium, with deposits mainly in East Africa.
Many gemstones today are treated with various methods to improve color and quality. Learn about the latest treatments and how they are detected.
Alternative metals such as stainless steel, tungsten carbide and titanium can be used to make modern jewelry. Read more about other metals for jewelry-making
Explore the vibrant world of turquoise gemstones, from their ancient history in Persia and Egypt to global sources and unique properties.
The Asscher cut is a modified emerald cut with a square shape, cut corners and a deep pavilion. The result is greater brilliance and fire
Gemstone Treatments are nothing new, but beryllium gemstone enhancements (Be heated) to improve color is a recent innovation which made gems more affordable.
These are important technical terms in gemology, but they are often misused. Learn how to use these terms correctly to describe gemstones.
Explore the world of aquamarine gemstones with tips on buying, differences from emerald, durability, color evaluation, and historical legends.
Gemstones are weighed in carats, while the purity of gold is measured in karats.
Many gemstone are certified to guarantee their authenticity. But not all gem certificates are created equal
All about gemstone clarity and cut in precious and semi-precious gemstones. Learn how colored gems are graded for clarity - and about the many gemstone cut...
Gemstones are classified by species, groups, types and varieties; and are assigned to the 10 mineral classes. Learn all about Classifying Gemstones.
Color change fluorite is a rare gem that displays a color change under different lighting conditions, often from blue in daylight to purple under incandesc...
Clarity grading for colored gemstones is not as simple as for white diamonds, colored gemstones are categorized into 3 types, and are then graded for clarity
Concave cutting is a recent innovation that uses curved rather than flat facets, resulting in a more brilliant gem. But not everyone is impressed
Ever since the discovery of paraiba tourmaline, the market is excited about copper-bearing gems. What's so special about copper?
Cubic zirconia, a synthetic gemstone, became the most successful diamond simulant on the market
The culet is the tiny facet at the very bottom of many faceted gemstones. Some gems are cut with a closed culet.
Gem treatments should always be disclosed, but not all enhancements can be detected, even by the best gem labs
Learn how to identify synthetic quartz with expert techniques, from visual inspection to advanced spectroscopy. Explore our comprehensive quartz guide and synthetic quartz overview for more insights.
Discover how diamond and graphite, both made of pure carbon, exhibit vastly different properties due to their unique atomic structures.
Diffusion treatment of gemstones is controversial, and may affect the ability to recut the stone in the future.
Clinohumite is a rare mineral and an especially rare gemstone. It is a member of the humite group of minerals, which includes humite, clinohumite, chondrod...
Druzy (druse or druzy) refers to encrustations or clusters of minute crystals in a matrix
Discover the common treatments for emerald gemstones, including cedar oil processes and modern fillers, to enhance clarity.
Explore the world of Epidote and Unakite, two intriguing minerals known for their unique characteristics and diverse applications in gemology.
The art of faceting enhances the brilliance and luster of gemstones. Buy faceted gemstones online at GemSelect.
Rhodolite, the rose-red to violet-red garnet, is a mixture of almandite and pyrope. It has the best red of any garnet.
Fracture filling is a common enhancement for emeralds, turquoise and a number of other gemstones. Learn about fracture filling and other gem enhancements a...
Why are so many fracture-filled rubies being offered in the market? Should you buy one?
A GemSelect guide to colored gemstone anatomy, learn how to identify a gem's pavilion, girdle and crown, and about different cutting styles and why they a...
A comprehensive glossary of terms used to describe colored stones, precious and semi-precious gems, minerals and gemstone jewelry.
Like diamond, colored stones are graded by the 4 c's. Carat weight is very important when it comes to gemstone value, along with color, clarity and cut - ...
GemSelect grades colored gemstones according to the following clarity scale: IF, VVS, VS, SI and I1, type 1, type 2 and type 3 should also be taken into account
Chart with cleavage ratings for more than 110 varieties of gemstones. Learn which gemstones have perfect cleavage and which have none at all.
A gemstone's color is its most defining characteristic. When deciding upon gemstone color you want to consider hue, tone, and saturation
Color saturation, sometimes known as chroma, is a measure of the purity or intensity of color hue. Highly saturated colors are highly valued in gemstones.
Learn how gemstone cutting transforms rough stones into brilliant gems. Discover cutting styles, process, and how cut affects beauty and value.
Looking for gemstones with significant fire? Here is a chart that ranks many gem varieties by their dispersion or fire.
A gemstone doublet is a composite stone made up of a natural gemstone and a less expensive material. Opal doublets are commonly found in the market.
What is the toughest gemstone? Which ones are easily scratched? These questions are many more answered in our informative article on gemstone hardness. Moh...
Hardness is only one measure of a gem stone's durability. Learn what other properties are important.
Trying to identify gemstones has become more challenging with the advent of new treatments and synthetics. What once was an art has become a science.
The most comprehensive library of gemstone information on the internet. Info on more than 80 varieties of gemstones.
In the gem trade, gemological labs have the last word in gemstone identification. A recent lawsuit shows that might not always be true.
Discover all Gemstones Names and Investigate the origins and meanings behind the fascinating and often bizarre names of gemstones we love and desire.
Well-cut faceted gemstones display 3 different illumination effects: brilliance, scintillation and fire
You may think shape, cut and facet all mean the same thing but read this article to discover the differences between pear shape, rose-cut and a faceted pavilion
Gemstone testers are becoming useful. But they are still no substitute for a trained gemologist.
Some marketing names for gemstones have succeeded; others, thankfully, have failed.
The Federal Trade Commission defines the rules for disclosing gemstone treatments. These rules may not go far enough
Stabilization and impregnation are gemstone enhancements that improve the hardness, density, color and durability of naturally fragile gemstones, especiall...
Diamonds are the most famous sparklers but there are a few gemstones such as zircon and sphene that could be even more brilliant. See our top ranked stones...
The term -gentle heat- for the heat treatment of sapphire and ruby is seriously misleading, and should be avoided
Discover Green Zircon's unique properties, symbolic meanings, and jewelry uses. Learn expert tips for buying and caring for this vibrant gemstone.
Some gemstones are routinely heated to improve their color and clarity. Learn how heat treatment works and how it can be detected.
Gem-quality hemimorphite is usually blue or green, and bears some similarities to chrysocolla, smithsonite and turquoise.
The briolette, a pear-shaped gemstone with geometric facets, is one of the oldest styles of cut gems.
Most gemstones form in the Earth's crust. Only two gemstones, diamond and peridot, form in the mantle. Learn about how gemstones form.
Some gemstones get their color from their essential chemistry; others from trace elements or impurities. Learn how the different gem varieties get their color.
Discover hydrothermal quartz, a lab-grown synthetic quartz used in technology and jewelry. Learn about its production, applications and expert insights.
Discover the rarity, stunning colors, captivating pleochroic properties, mining locations, and market value of iolite. Dive into what makes this unique gemstone
All about the irradiation of gemstones to improve their color.
Discover the properties of kyanite, including its variable hardness due to anisotropism, stunning blue hues, industrial uses, and mining locations worldwide.
Explore the captivating iridescence of labradorite, its history, colors, luster, cutting techniques, and jewelry ideas.
Gemstone color appears differently under different kinds of light. But how many kinds of light are there?
Discover how colorless topaz and quartz are transformed into vibrant mystic gems using advanced thin-film coating technology. Learn about the process.
What is the difference between a mineral, a rock and a gemstone? You'll find some answers here.
Buy loose gemstones even if you can't spell padparasha, pariba, saphire, alexanderite, dimond, tanzinite or andasine.
Most gemstones are crystals but some of our most famous precious gems are organic in origin, forming from animal or vegetable - pearls, amber, coral and am...
It is not often that a new gemstone appears and the arrival of the vivid neon blue of the Paraiba Tourmaline took the world by storm shortly after it was d...
Pezzotottaite, a rare gem first discovered in Madagascar, is often confused with red beryl.
Planetary gemologists prescribe gems based on astrological principles. Using the right gems is said to enhance health, wealth, power and popularity.
Some gemstones display different colors when viewed from different angles. Andalusite, iolite, kyanite, kunzite, sphene and tanzanite exhibit pleochroism t...
Prongs and bezel settings have advantages and disadvantages. Learn about prong (or claw) settings and bezel settings for gemstone jewelry.
Scientists are using Raman spectroscopy to identify gemstones and minerals with a Star Trek-style tricorder device.
Sillimanite is a rare collector's gemstone that is colorless, grayish-white, green, bluish or brownish hues. Transparent, faceted sillimanite gems are ext...
A chart of the refractive indices for more than 200 varieties of gemstones. Find quickly all the data you need.
Learn how to evaluate star gemstones, and why the star may not be easy to see under diffused light. Gemstones that display the star effect, known as asteri...
The world of semiprecious stones is incredibly diverse. Some are as rare and valuable as any precious stone. Others are very affordable.
Fake gemstones may be synthetics or simulants. Learn how to identify the difference between these.
Diamond, garnet and spinel are well known as belonging to the small group of singly refractive gemstones. But there also are some lesser known members of t...
Specific gravity is the term for the relative density of a gemstone. This chart shows the specific gravity for more than 60 varieties of gemstones.
Uncover what is special about Spessartite Garnet. Explore its vibrant colors, origins, and unique properties that make it a gemstone connoisseur's treasure.
Sphene is one of very few gemstones with an adamantine or diamond-like luster. Sphene's dispersion or fire even exceeds diamond.
Spudomene is a major source of the lithium found in batteries around the world but the pink gemstone Kunzite is a spudomene and so is the green Hiddenite
Star diopside is known in the gem trade as the Black Star of India. Not as well known as chrome diopside, but special and unique with asterism chatoyancy -...
Star sapphire and star ruby are examples of gems that exhibit asterism or the star effect. Learn why some gemstones exhbit this rare phenomenon.
Discover the story of synthetic emeralds pioneered by Carroll Chatham using the flux method. Learn about their superior durability compared to natural emeralds
Moissanite is the latest diamond simulant to hit the market, with a hardness and density more diamond-like than cubic zirconia
In 1902 the French chemist Verneuil invented the flame fusion method for creating synthetic corundum. It is still being used today.
Taaffeite is one of the rarest gem varieties in the world. It has many similarities to spinel, but is doubly refractive
Tension settings use compression to hold a gemstone in place. The designs are stunning, but are these setting secure?
An attractive red feldspar called andesine has attracted a lot of attention in the gems world. What is really known about andesine?
Explore the captivating world of spinel gemstones, from their unique composition and vibrant colors to mining sources and comparisons with ruby and sapphire. Uncover why this durable, untreated gem remains a secret favorite among collectors and enthusiasts.
Explore the diverse world of quartz gemstones, including macrocrystalline types like amethyst and citrine, and cryptocrystalline varieties.
Discover Color Zoning in Gemstones with our in-depth guide. We explain how this fascinating phenomenon affects the beauty and value of precious stones.
Some gemstones, including diamond, topaz, tanzanite and fluorite, have perfect cleavage. Learn about why this is important.
There are many untreated colored gemstones that come from the mines to the market completely natural and unenhanced, such as opal, tourmaline, quartz, spin...
Some varieties of gemstones are never treated, and they represent exceptional value in today's gem market.
Explore uvarovite garnet, the rarest garnet with a vivid emerald-green hue. Learn about its unique properties, Russian origins, jewelry uses, and care tips.
Conventional wisdom about colored gemstone inclusions is that less is more. But some inclusions are valuable.
Explore the definition of natural sapphires, differences from synthetics, common treatments like heating and lattice diffusion, and their impact on value.
What are gemstone cabochons, and why are some gemstones cut as cabochons and others as faceted gems?
Explore the ancient origins of zircon, dating back 4.4 billion years, and delve into zirconology—the scientific study of this remarkable gemstone. Learn about its gemological properties, optical features, historical uses, and more in this informative guide.
Zultanite, Csarite and Diaspore are all names for a color change gemstone from Turkey. What is color change diaspore and why does it have many names?