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Clarity is the second most important of the 4 c's when considering Tsavorite quality. Clarity simply refers to how inclusion-free a gemstone is. Once again, the most universally accepted and most documented system is the GIA system but there are also numerous other trade based systems in use. Tsavorite is classed as a Type 2 gemstone by the GIA and as such is grouped amongst stones regarded as "usually included". This means that because of Tsavorite's geology, the majority of stones have some inclusions. Unlike Tanzanite, which is a Type 1 gem, it is not essential that it is loupeclean Below is a chart showing the GIA clarity grading system.
VVS : This is the top grade in the GIA system. Tsavorite is classed by the GIA as a "Type 2" gem which means it is graded less strictly than Type 1 gems like Tanzanite but more strctly than Type 3 gems like Emerald. VVS Stands for Very very slightly included and whilst many VVS Tsavorites are loupeclean they can contain minor inclusions classed as somewhat easy to see with a loupe (10x magnification) and usually invisible to the unaided eye. Typical minor inclusions may be small included crystals, fine needles, liquid inclusions (known as fingerprints), tiny feathers.
VS : This stands for Very Slightly Included and these stones are characterised by noticeable inclusions of moderate size which are easy to see under 10x magnification and sometimes visible to the unaided eye. Typical inclusions may be liquid inclusions, needles, small feathers, small chips.
SI1 - SI2 : This stands for Slightly Included and these stones are characterised by obvious inclusions which are large and/or numerous under 10x magnification. In SI1 they are apparent and SI2 very apparent to the unaided eye. Typical inclusions are large included crystals, large liquid inclusions, feathers, dense clouds. As a rule, if you can see inclusions in the photograph displayed on gem sites (such as in those displayed below) then the stone is most likely an SI or lower.
I1-I2-I3 : The lowest grade. Stands for Imperfect. These stones are characterised by inclusions that have a negative effect on either appearance, durability or both. At I1 there is a moderate effect on either factor, I2 a severe effect on either factor and I3 a severe effect on both factors.
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When purchasing Tsavorite there are several factors you need to consider - these are the 4 c's - Color, Clarity, Carat Weight and Cut.
Color is the most important of the 4 C's when considering Tsavorite quality. It can also be one of the most confusing aspects as you surf the web as so many different sites use different terms/grading systems and it is difficult to effectively compare one with another. Also, Tsavorite has a variety of colors which are considered top and this can be confusing most especially when trying to make comparisons. We have tried to help make this clearer by displaying a suite of Tsavorites below demonstrating color quality:
A suite of top Tsavorites showing excellent saturation and tone levels
A suite of low grade Tsavorites showing low saturation and tone levels
A suite of low grade Tsavorites showing over saturation and tone levels
The pictures above do an adequate job of demonstrating color in Tsavorite. The top colors show how a top level of saturation of color produces a vivid deep color and when combined with top levels of tone produce a beautiful gemstone. The pictures below indicate what happens when the color is de-saturated and the last row show Tsavorite that is too saturated and have high tone levels. The GIA color grading system is the most widely accepted color grading system for colored stones and was developed around grading saturation and tone levels. To read more about GIA grading click here to open a sample certificate and then click the cursor on the color grade to get a full description of how GIA color grades are constituted.
| GIA GRADES CONSIDERED TOP QUALITY |
GIA GRADES CONSIDERED TOO LIGHT |
GIA GRADES CONSIDERED TOO DARK |
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| yG 5/5, yG 6/5, vslyG 6/5, slyG 6/5, bG 6/5, slbG 6/5, bG 5/5, G 5/5 |
yG 5/4, yG 4/4, vslyG 4/4, slyG 4/4, bG 5/4, bG 4/4, slbG 4/4, G 4/4 |
yG 7/6, yG 7/7, vslyG 7/6, slyG 7/6, bG 7/6, bG 7/6, slbG 7/6, G 7/6 |
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TRADE GRADES
Exceptional
Vivid Exceptional
Deep Green
Vivid Green
Extra fine grade |
TRADE GRADES
Light Green
Bright Light Green
Medium Green
Apple Green |
TRADE GRADES
Dark Green
Dark Tsavorite |
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Tsavorites are not generally available in large sizes. even 1 carat fine stones are rare. On average, it takes over 1 ton of gem bearing rock to extract under 5 carats of fine 1 carat pieces. Fine stones over 2 carats are rare and over 3 carats they become very rare in the fine qualities. Many stones are cut to retain weight and sacrifice quality for size so be careful when buying large stones that you are not buying simply for size and that the clarity and color are also fine. Carat weight affects the price generally as weight increases stones in the same quality bracket will cost more per carat. In Tsavorite, because of the huge rarity of large stones, this price jump is marked.
Although it has the least impact on value of the 4 C's cut is still important. In the market, tsavorites are found in a variety of shapes and cutting styles. Ovals and cushions are the most common, but rounds are also seen, as are other shapes, including emerald cuts, trillions, etc. Cuts should be proportional - you don't want to pay for a stone with alot of weight in the pavilion for example when this weight will be invisible in a setting.
FAKES / SYNTHETICS / IMITATIONS : Tsavorite has never been synthesized, but a number of imitations exist. The most common is green glass. Another is synthetic Spinel (a manmade imitation) Laymen can easily be fooled so always buy from a reputable dealer, preferably a member of the ICA (International Gemstone Dealers Association) which has a strict code of ethics.
ENHANCEMENTS : None. Tsavorite is one of the most "honest" of all gems on the market today. It is simply cut, there are no treatments, enhancements or synthetics. It is one of the most endearing features of this wonderful gemstone.
WHAT IS KURANZE TSAVORITE? : There are a number of Tsavorite mines in East Africa. The majority of deposits contain Tsavorite colored by Vanadium. However, one deposit, in a place called Kuranze, also contains Chromium. This gives the stones from this deposit exceptional color, often with a trace of blue in the green like the finest Muzo Columbian emerald. This mine does not produce many stones and most that it does produce are small but material from this deposit is considered a cut above the rest.
You may also like to watch our multimedia presentation on why Tsavorite is superior to Emerald or about Tsavorite history & care for further information :
Tsavorite versus Emerald
Tsavorite History & Care
Or alternatively we can offer some select fine Tsavorite for discerning buyers:
Buy Fine Tsavorites from our private collection
You may also like to read more about Tsavorite on the ICA website. The ICA (International Colored Gemstone Association) is a non profit institution dedicated to educating the public about colored gems. It has a strict code of ethics.Our company has been a member for many years.
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