So you have picked out your Alexandrite and are anxiously awaiting its arrival to your home. When you receive the parcel you excitedly open it expecting….
Different gem labs grade clarity in colored gemstones differently. Khazargems uses the GIA (Gemological Institute of America) Colored Gemstone Grading Scale. According to the GIA – perhaps the world’s best known and trusted Gem Association and Lab, there are THREE different charts for grading colored gemstones (and Diamonds). Perhaps the one that most jewelers are familiar with is the Type 1 Gemstone Chart, which includes the grading of Diamonds. The Chart that a gemstone is graded in is dependent on the physical characteristics of the majority of a particular gemstone; such as Alexandrite being graded as a Type 2.. The charts and the gemstones that fit into each are as follows:
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Other labs grade gemstone clarity as: Fine, Good, Fair, Poor; or Eye clean, Slightly Included, Moderately Included, Included. Some labs even describe clarity as: Transparent, Translucent, or Opaque.
Khazargems uses the GIA grading because it is more descriptive and has more divisions in the grading.
EXPLANATION OF COLOR IN GEMSTONES
It is difficult to describe coloration so that it means the same to all individuals. Even the pictures that we take are a) static- that is the light reflected through one plane because the gem is not moving, and b) monitors show color differently depending on the brand and how the brightness and other adjustments are set. Coloration in an Alexandrite is the gem’s MOST IMPORTANT characteristic in both the daylight coloration and the color change coloration. Khazargems describes color through:
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Alexandrite is a Phenomenal Gem that is a gemstone that naturally displays a different color depending on the wavelengths of the light passing through the stone. The strength of the color change and the coloration of Alexandrite are the MOST IMPORTANT characteristics of this gem. Khazargems grades color change on the following scale:
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Color-change % approximately translates to:
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BRILLIANCE in a gemstone is described by the amount, or percentage, of white light that reflects and refracts from a gemstone while looking down at the table (the top) of the gem from above. The greater the brilliance the more alive the gem appears. This is different from Sparkle, which is the myriad sparks of color that are seen when a gem is rotated in light.
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Brilliance (Approximatel)y Translates To:
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WINDOWING – most Alexandrite are cut by native gem cutters that have been taught from father to son for generations. Since Alexandrite is such a rare gemstone and is found in smaller crystal size, the rough is cut with the least waste to create the largest gemstone possible. A majority of Alexandrite that is faceted in the Oval shape will have windows where the faceting under the gem does not reflect the light back up to viewer in a dispersal pattern. In the following gems windowing can be viewed in the center of the stone:
Large Window

Medium Window

Small Window
Alexandrite that have beautifully saturated coloration and strong color change with little or no windowing command a premium in pricing since a piece of rough that can be faceted into a One Carat Oval Alexandrite with windowing will generally be about 0.65 carat to 0.75 carat if cut without windowing.
Size – The Alexandrite you receive is NOT going to be the size you see on your computer monitor. Khazargems takes pictures of the gemstone or jewelry next to a millimeter ruler to help you see the size. Khazargems also gives the dimensions of the gem inmillimeters (mm). Millimeters are not inches! One inch equals 25.5mm. A gemstone that is 8mm x 6.5mm will equal 5/16 inches x 1/4 inches approximately. We measure in millimeters because it is the common measurement of all major gem labs and mines for gemstones.
Viewing YOUR Alexaxdrite – Now that you know what to expect when you open your parcel to view your Alexandrite, also know that to show the best GREEN color, take the gem outside and view it. To see the best color change look under low wattage incandescent lighting (not the “blue” bright white bulbs). Rotate your Alexandrite to get the most impact from all the facets and axis.
Mixed lighting sources can create mixed coloration from greenish bluish grey to purple gray lavender with flashes of red, violet, blue, green.
Experiment and you will find that your Alexandrite has its own unique identity depending on the light it is in and how it is viewed. These are your Alexandrite’s identifying characteristics and are individual to each stone. Enjoy your incredible wonder of nature!!!
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