Color is the dominant feature of a colored stone, and thus is weighted in the grading process. Color grading is subjective. Colored stone color grading, for this appraisal, was performed using the GIA Square software system. The color is described in terms of Hue, tone, and saturation.
Clarity - Transparent colored stones are divided into three type classifications depending on crystal growth characteristics, and then graded within their type class, for clarity.
The G.I.A. grading system for colored stones lists clarity type classifications as Type I, Type II, and Type III. The classifications are defined as follows:
Type I These are gems that grow extremely clean in nature and usually have no eye-visible inclusions. An example is Aquamarine.
Type II These are gems that typically grow with some minor inclusions in nature and the inclusions may be eye-visible. An example is ruby.
Type III These are gems that typically grow with many inclusions in nature and the inclusions are usually eye-visible. An example is emerald.
The table below is published by THE GUIDE-REFERENCE MANUAL, copyright 2004, and explains the clarity grading system as it applies to the classifications of transparent colored stones.
Cut - Colored stones are also graded for cut. Cut grading includes observance and qualification of brilliance, proportions, bulge, overall symmetry, and finish.
The Guide Grade listed on this appraisal report consists of a compilation of the color grade, clarity grade, and cut grade of the subject gemstone.
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