Green emeralds are a variety of the gemstone beryl and have been highly prized since pre-historic times.

Color  - hue, tone and saturation
Clarity - visibility of inclusions
Cut -how well the stone is cut

Carat - The size or weight of the gemstone

A fine emerald can be more expensive than a high quality diamond of the same carat weight.
Emeralds are green members of the popular beryl family of minerals. The green color occurs when pure, clear beryl contains either chromium or vanadium.

Beryl occurs in many other colors, with shades dependent on the impurities that Mother Nature has mixed into its otherwise clear formula. Blue beryl is known as aquamarine. Pink shades of beryl are known as Morganite. Yellows are often simply called yellow beryl and golden beryl. The term bixbite refers to red beryl, a variation that's even more rare than emeralds.

Emerald hardness on the Mohs scale ranges from 7.5 to 8. As a reference, turquoise ranges from 5 to 6; diamonds are the hardest substance, at 10. Sponsored Links
Rare Emeralds Since 1946

Even though emeralds are relatively hard stones, the presence of cracks and inclusions can affect their durability.

Emerald is the birthstone for May and is the traditional gift for the 55th wedding anniversary.

Colombian emeralds are among the world's most beautiful, with rich grass-green coloring that's often kissed with a touch of blue. Quality emeralds are also found in India, South Africa, Afghanistan, Pakistan, Russia, and Zimbabwe. Recent finds in North Carolina may provide us with quality emeralds if the mine continues to produce stones.

Emerald History and Folklore

Emeralds are traditionally thought to enhance the clairvoyance of their wearers.

Egyptian emeralds were introduced to the world about 4,000 years ago, but the stones from those mines are a duller green and are not considered high quality by today's standards.

Mummies were often buried with emeralds and the gems were popular in ancient Rome, but some think that many of the stones called emeralds in ancient times were actually peridot.

Traditionally, emeralds are worn to promote healing and enhance love and contentment.

Most emeralds are treated to enhance their appearance. Even though treatments are common and accepted, they should be disclosed.

Nearly all emeralds are treated with oils or epoxy resins to fill-in surface cracks, making the cracks less visible and improving transparency.

Some oils are clear, some are tinted green to make the gems more vivid.
Most jewelers tell us to avoid cleaning emeralds with ultra-sonic devices, because that process can remove coatings.

When high-demand gemstones are scarce and costly, humans attempt to create products that look like the real thing. Emeralds can be lab-grown synthetics, which do have the same chemical composition as a stone grown in nature, or they can be genuine stones combined in ways that make a small sliver of gem look like a larger specimen. What you think is an emerald might even be a fake made of glass or another material.

Synthetic Emeralds. The way they are grown has changed, but synthetic emeralds have been produced for many years. Some of the stones even have inclusions that make them look natural. Some dealers may claim a synthetic is "real," and that is technically correct, since true synthetic gems have the same chemical characteristics as their natural counterparts, but a reputable jeweler will disclose that a gem is lab-grown. Always ask if gemstones are created or natural, and if you are buying an expensive stone, have it checked by a lab.

The grading is done on the majority of these 3 results.

Color
Color is the single most important factor when evaluating colored gems. Basically, the more attractive the color seen, the higher the value. Bright, rich and intense colors are valued over those that are too dark or too light. Colors that are dulled by tones of black, gray or brown are regarded as less desirable. The colors seen should ideally remain attractive regardless of prevailing light conditions. Whether viewed indoors, outdoors, by day or by night, a gem should always remain beautiful.

The mixing of color hues into combinations, such as evergreen and turquoise and aqua and grass green in Emeralds is attractive and value enhancing. Some people ask me if emeralds from Africa are a different color of green than emeralds from Brazil. They are not-when you see the two next to each other you cannot tell the difference. Emeralds from both countries come in all different shades of green. Being from one country versus the other makes no difference in the value of the emerald. You will see many different terms describing color on many different websites such as top green, best green, fine green, nice green, rich green, green-blue, blue-green, greenish blue, bluish green, etc.,. Although specific colors hues can affect the prices of gems, personal preferences are more important. Think of how the gem will look mounted, how it catches the light at different angles. Think about how you feel about the color-do you prefer a dark green or light green.

Clarity
Most gems contain tiny natural features called inclusions. Mostly microscopic in nature, they are most easily glimpsed under magnification. Inclusions that don’t interfere with the brilliance, sparkle and fire of a gem don’t affect the value.

Many gems have tendencies to be more included than other varieties. For example, Emeralds are known to be far more included than Sapphires and this should be taken into account when making your selection.

The clarity of gems is determined by judging the amount and location of inclusions seen. Basically, the higher the clarity grade, the higher the value of the gem.

Emeralds are called Type III Gemstones and go by this type of Grading below concerning inclusions.

Type III Gemstones : Type III stones are almost always included and show eye-visible inclusions, but even specimens with obvious or prominent inclusions are often faceted for use in jewelry.

VVS, Type III - describes Gems that are as close to flawless as is found in the particular type III gemstone, a gemologist under favorable lighting conditions can see small inclusions (small feathers, light silk, light gardin, etc.) which are usually obvious when viewed with 10x magnification, but you will probably not readily see these inclusions to the unaided eye, except on larger stones.

VS, Type III - describes Gems that are very clean for the particular type III gemstone, a gemologist can see small sized inclusions (small fissures, light gardin, etc.) that is usually visible with the unaided eye without magnification. Larger Emeralds can have medium sized inclusions and still be graded VS Type III.

SI, Type III - describes Gems that are lightly included but the inclusions are not a negative for the particular type III gemstone, a gemologist can see moderate and/or numerous small inclusions (fissures, gardin, carbon, etc.) that are visible to the unaided or naked eye without magnification.

I1 to I2, Type III - describes Gems that have inclusions centrally located or numerous inclusions that are visible to the unaided or naked eye without magnification. Most Good quality Emerald will be in the I2 to I3 category.

I3, Type III - describes Gems that have very obvious inclusions that are very visible to the unaided or naked eye without any magnification. This grade of excessively included gem may have some durability problems.

Cut & Polish
Unlike Diamonds, colored gems possess variable optical properties and are not cut to a uniform ideal. A well-cut colored gem exhibits even color, a minimal number of inclusions, good brilliance and shows the majority of Carat weight when viewed from the top. A well-cut gem should also exhibit good symmetry and polish condition. Facets should be aligned straight in relation to the gem’s girdle and also to each other. Polish condition should be good with no visible surface pits and polishing lines.