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:

GIA Type 1 Clarity Chart

VVSVery Very Slightly Included – Minute to not detectable
VSVery Slightly Included – minor
SI1Slightly Included – NOTICEABLE to obvious
SI2Slightly Included 2 – OBVIOUS to noticeable
I1Included 1 – Prominent – moderate effect on appearance or durability
I2Included 2 – Prominent – severe effect on appearance & durability
I3Included 3 – Prominent – severe effect on beauty, transparency & durability
Type 1 Gemstones are gemstones that are normally found to be clean.  This includes gems such as Amethyst, Aquamarine, Blue Topaz, Citrine, Kunzite, Tanzanite, Yellow Beryl, Yellow Chrysoberyl, Diamond.

GIA Type 2 Clarity Chart

VVSVery Very Slightly Included – Minor inclusions
VSVery Slightly Included – NOTICEABLE to Obvious
SI1Slightly Included – Noticeable to OBVIOUS
SI2Slightly Included 2 – Obvious to Prominent
I1Included 1 – Prominent – moderate effect on appearance or durability
I2Included 2 – Prominent – severe effect on appearance & durability
I3Included 3 – Prominent – severe effect on beauty, transparency & durability
Type 2 Colored Gemstones by their nature have natural inclusions. (Inclusions are the norm) This includes gems such as Andalusite, Crysoberyl, Alexandrite, Corundum (i.e. Sapphire and Ruby), Garnet, Peridot, Quartz, Amethyst, Citrine, Ametrine, Spinel, Tourmaline, Zircon.

GIA Type 3 Clarity Chart

VVSVery Very Slightly Included – NOTICEABLE to obvious
VSVery Slightly Included – Noticeable to OBVIOUS
SI1Slightly Included – OBVIOUS to prominent
SI2Slightly Included 2 – Obvious to PROMINENT
I1Included 1 – Prominent – considerable effect on appearance or durability
I2Included 2 – Prominent – severe effect on transparency or durability
I3Included 3 – Prominent – severe effect on beauty, transparency & durability
DeclassStones not transparent because of inclusions
Type 3 Colored Gemstones by their nature have many natural inclusions. (Heavily Included is the norm) This includes gems such as Emerald, red Beryl, Rubellite Tourmaline.

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:

 

Color is described in gems through:

  • Hue – the exact color in the spectrum (red, orange, yellow, green, blue, indigo, violet); Intensity or Saturation- the brightness or dullness of the color.
  • Tone – how light or dark the stone is (how much black or white is present).
  • Distribution – the evenness of color throughout the stone (Zoning).

When reading a description of the color of a gem if there are mixed hues, the predominant hue is Capitalized and the lesser hue is lower case. For example: bluish-Green; Green is the predominant color and blue is the lesser (underlying) color.

 

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:

 

Color is described by Hue. Where there are mixed hues, the predominant hue is Capitalized and the lesser hue is lower case. For example: bluish-Green; Green is the predominant color and blue is the lesser (underlying) color. 

 

Color-change % approximately translates to:

95%Vivid – Easily Changes, Extremely Strong
75%Strong – Changes Easily
50%Moderate – Apparent Color Change
30%Weak – Subtle Color Change

 

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.

 

Brilliance is described by the amount, or percentage, of light that reflects and refracts from a gemstone while looking down at the table of the gem from above. The greater the brilliance the more alive the gem appears. 

 

Brilliance (Approximatel)y Translates To:

ExcellentFull brilliance throughout the gem.
FineBrilliance through 90% of the gem.
GoodBrilliance through 70% of the gem.
FairBrilliance primarily on the edge of the gem.
PoorBrilliance seen only in strong light.

  

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!!!