Gem Facts

Language of Colored Gemstones

Colored gemstones are among the most individual of nature's creations: beautiful crystals, with no two alike. Although some gemstone varieties have been treasured since before history began and others were only discovered recently, all are nature's gifts to us. A gemstone is the naturally occurring crystalline form of a mineral which is desirable for its beauty, valuable in its rarity, and durable enough to be enjoyed for generations.

Colored gemstones are beautiful, transparent jewels. Their different color, shapes and variety, are what make them so valuable. Some gemstones are rarer than others. The blue sapphire is rarer than the blue topaz. Carat size, custom faceting, excellent color and variety of the gem would definitely make it a rarer gemstone than something bought at a local jewelry store.

New colored gems are being discovered each year. Tanzanite, Tsavorite garnet and Mandarin garnet are recent newcomers.

Color in Gems:

Color is the most important factor to consider when purchasing a gem. The more pure and vivid the color, the more valuable the gemstone.

Color is described in three components – hue, tone and saturation. Hue is the dominant color and any additional colors visible in a stone. Ex.: – orangy Red or bluish Green. Tone is the lightness or darkness of the color. Saturation is the strength of the color. Vivid color being the best.

Gemstones are the most intensely colored natural mineral crystals on earth. Gems come in a rainbow of different colors. Gems have even lent their names to colors. Everyone knows the colors, Ruby red, Emerald green or Sapphire blue... But there is a more extensive selection of colored gemstones to select from, more choices in each color:

Gemstone Families:

Garnet : Everybody knows Garnet as being a red gem. Did you know that garnet is available in many other colors? It comes in red, yellow, green and orange. Garnet can be mistaken for more expensive gems. Green garnet, Tsavorite is the most beautiful emerald green, almost always mistaken for emerald. It is clearer, more brilliant and durable than emerald. There is Demantoid garnet, a rarer green garnet that has the fire near that of a diamond. For people that can not afford Emerald, green garnet would be a fine alternative and a better price.

Almandite, Rhodolite, Malaya, Spessartite and Pyrope, garnets reds are often mistaken for rubies. There is a rare Color Change Garnet that appears red in incandescent lighting to blue in daylight. The new find, Mandarin garnet, a scrumptious orange color, yummy.

Beryl : Green Emerald, one of the rarest of the beryl family. The higher quality emerald should be the color of fresh grass, the purest green with just a hint of blue. Red Beryl (bixbite) is even rarer, a highly prized gem. Aquamarine, clearer and more brilliant than emerald, ranges from a light blue, to a deep blue. Morganite, pale pink to an orangy pink, this gem’s beauty and limited ability makes it a favorite for collectors.

Tourmaline : Tourmalines versatility and range of colors makes it a favorite gemstone to many. It is available in ever color. Chrome Tourmaline, A rare green color. Rubellite, Deep pink to red. Indicolite, deep blue, with a hint of green. There is a bi-color(2 colors) and a tri- color (3 colors) tourmalines. Watermelon tourmaline, that looks just like a slice of watermelon, red on the inside, with a green rind around it. Then there is the famous Paraiba Tourmaline, from Paraiba, Brazil, the finest being the color of windex glass cleaner. Beautiful but very, very expensive.

Phenomenon in Gems:

Color Change – Difference in a gem’s body color in different types of light. (Incandescent/fluorescent) Alexandrite, garnet, spinel and sapphire can show color change.

Pleochroism – Some gems have more than one body color seen in different directions. This can be seen when gem is rocked back and forth. Gems like tourmaline and sapphire show two pleochroic colors Tanzanite, iolite and andalusite can show three.

 Clarity:

Inclusions help a gemologist identify a gem, certain types of inclusions are characteristics in specific types of gemstones. A certain inclusion may provide positive identification to that gem, such as a lily pad type of inclusion found only in Peridot. Inclusions are nature’s fingerprints in a gem.

Inclusions that are too numerous and easily noticeable can weaken the gem, reducing the price significantly. Inclusions can have an adverse effect, increasing the price if they prove the identification of the gem. They can also prove origin such as, Kashmir Sapphire, Columbian Emerald and Burma Ruby.

A gemstones freedom from inclusions (blemishes) is part of the gem’s grading score. It is based on how visible the inclusion is, where it is located on the gem and the size of the inclusion. The type and placement of the inclusion in a colored gem is more important than the inclusion itself. Ex.: A large feather (fracture) very close to the surface of the table (top) of a gem, could prove to be dangerous, it could weaken that gem’s durability. A future bump could break that stone. It could also cause an unsightly irradiance from the fracture (feather) that would detract from the gem’s beauty, reducing the value. But that same feather if it happened to be under the crown facets would not be so noticeable or risk the gems durability.

Some grade colored stones with the same nomenclature as diamonds. ( FL-Flawless, VVS- Very Very Slightly Included, VS- Very Slightly Included, SI- Slightly Included, I – Numerous Inclusions).

When grading gems a gemologist uses a loupe that is a special type of magnifying glass tool helpful for checking a stone for noticeable inclusions more closely. Even with a loupe one must have the knowledge and skill to see and understand the many telltale indicators that an experienced gemologist can see.

A loupe must be 10X magnification; the United States Federal Trade Commission requires grading to be done under 10X magnification. Any inclusion that one cannot see with a 10X loupe is considered non-existent for grading purposes.

Colored gemstones are also judged by their beauty and rarity.

Looking through a 10X loupe, I grade my colored gemstones using this grading system:

Excellent: Flawless, No inclusions

Very Very Good: Nearly flawless, minute inclusions, very difficult to see, difficult to locate under 10X magnification. Some call this Eye Clean

Very Good: Minor inclusions, may be difficult to see, fairly easy to locate under 10X magnification.

Good: Noticeable inclusions can be seen with the eye, will not detract or durability of the gem.

Fair: Obvious, large inclusions, so numerous they have a severe affect on transparency and brilliance and that could seriously affect the stones durability. I do not have gems of this caliber; I refuse to sell stones that should be considered aquarium gravel.

Inclusions:

 

Most Common: Feather – Inclusion with white feathery appearance.
Crystal – Mineral crystal inside gem.
Needle - Long thin inclusion.
Color Zoning – Visible internal evidence of crystal growth.

GIA’s Grading System:

Type I - Gemstones that are normally found to be clean Ex.: Amethyst, Aquamarine, Blue Topaz, Citrine, Kunzite, Tanzanite Heliodor (Yellow Beryl), Yellow Chrysoberyl.

Type II - Gemstones normally have a few inclusions. Ex.: Alexandrite, Andalusite, Iolite, Peridot, Rhodolite, Ruby, Sapphire, Spinel, Tourmaline and Tsavorite Garnet.

Type III - Gemstones that normally have inclusions, are not clean. Ex.: Emerald, Red beryl (Bixbite), Rubellite, (Red Tourmaline)

Gem Treatment:

I facet natural stones, majority which are not treated. Gems that have been treated or enhanced in anyway will be noted in the gem description.

The treatment of gems is generally to improve clarity and color. Most gemstones are treated to improve their appearance. A treated gemstone may also be called enhanced. Most common treatments are irradiation and heating.

Heating gems dates back over a 1000 years. This is using a degree of heat to alter color and clarity. Some heat treating is not detectable, generally heat treated stones are stable and usually permanent.

Irradiation is the use of neutrons, gamma or ultraviolet to alter a gemstones color. Usually irradiation is followed by the heating process. A good example of this is Blue Topaz, starts out a clear gem then treated to become the blue color.

Synthetic/Simulated Gems:

Synthetic Gems are fun to facet as they usually have impeccable color and clarity. All Synthetic Gems sold on this website will be clearly stated as Synthetic Gems.

A synthetic stone has the same physical, chemical and optical properties as a natural gem.

Simulated stones (Imitations) are an artificial copy of the natural stone, usually in color only. They are generally glass or plastic.

A Graduate Gemologist is trained to identify synthetics or imitations. It is sad to say there are scams out that misrepresent and fraudulently sell gemstones that are synthetics or imitations. As a Graduate Gemologist I have the knowledge and the equipment to verify each and every gemstone that I sell. You can buy with confidence, being assured of quality and the authenticity of the gemstone you purchase.

Cut:

This is the faceting of the gem, shape and design. Gemstones must be cut (faceted) well to attain their maximum potential for beauty. A well cut gem should be proportioned (accurate angles and measurements) and the polish of the gem should reflect the quality of workmanship. All of my gems are custom cut in unique designs that you will not find in retail stores.

When you look at a gemstone with your eyes, it should captivate you with it’s brilliance. Then you will know that it is well cut.

A well cut gem will give the best brilliance. This is when light enters the gem through the crown (top) reflects off the pavilion facets (bottom), bouncing upward to exit the crown. This is what you see, the gem’s brilliance, bright flashes of the gem’s body color.

A properly faceted gemstone will have tons of brilliance.

Faceted:

Is a style of cutting the gem that consists of placing many small facets at varying angles to one another following a certain planned design. A gem blueprint. The placement of angles and the shape of the facets is carefully planned so the gemstone’s inherent beauty, fire, color and brilliance is seen to it’s fullest advantage. A good cut will enhance the natural beauty of the gem and exhibit it’s finest color.

The rough stone emerges to become a lively colored jewel, a precious gemstone. It’s like Magic!

Commercial VS Custom Cut:

Commercial cut gems are cut overseas, the majority of gemstones are cut with crude equipment, therefore correct angles cannot be accomplished, resulting in uneven shapes and dull colors. Rounds, ovals and rectangles are the common cuts.

Carat:

Gemstones are measured by carats. The metric carat is an internationally used standard unit of weight equal to 1/5 (0.20) of a gram.

1 carat = 100 points (1 point =0.01 ct.). or 0.20 gram.

1 gram = 5 carats.

Large gems are more rare than small ones, so they often cost much more per carat, even if they are of equivalent quality.

Some gems weigh more than others because of their density. This is called specific gravity. The mineral material is heavier. Ruby is heavier than emerald. A 1 carat ruby will have different size than a 1 carat emerald. The ruby will be smaller as it is a heavier mineral.

Certain gems are more readily available in larger carat size ex. 10+ carats, Aquamarine, Amethyst and Citrine, because they are more common in larger sizes.

Scarcity and rarity in certain colored gemstones can affect a higher price per carat. This can effect the definition of being large for a colored gemstone.

Ex.: A fine 5 carat Red Spinel is a very large stone for it’s standards. A 10 carat Amethyst, well that’s a nice size gem.

A .91 carat, SI1, G color, diamond can sell way less than a 1.10 carat, SI1, G color, diamond. The per carat price will increase as it passes that 1 carat magical line. But if that same .91 carat SI1 diamond was Red in color, it would be worth a King’s ransom.

Precious and semi precious gemstones :

The gemstone business in the past was dominated by the "big three," Ruby, Emerald, and Sapphire. These gemstones have always been the most popular and considered the precious gems and all others semi precious. The truth is all natural colored gemstones are rare and precious. Prices are determined by the quality and availability of a certain gemstone.

The problem with semi-precious, and the reason why the jewelry industry has banned its use, is that it is quite misleading. Rubies, emeralds, and sapphires can sell for less than $100 per carat and a fine Paraiba tourmaline, for example, can sell for $20,000 per carat. Gemstone prices are determined by the quality and availability of that certain gemstone.

Appraisals:

An appraisal is an estimate of a gemstone's value. It can be helpful for insurance purposes.

Some appraisers are very skilled and reputable but, because anyone can call themselves an appraiser, some unfortunately are not. Look for a "Certified Appraiser."

Buy a beautiful gemstone; do not buy a piece of paper. Gemstones do store wealth and are an excellent way to pass down something fine and valuable to the next generation. Enjoy them today as well as in the future!