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Gemstone Grading System

 

SWiJ Gemstone Grading System (GGS)

 

·         Stone Clarity (7) - SC

1.      VVS – Very Very Slightly Included (Loupe Clean) – 10 Points

2.      VS – Very Slightly Included (Eye Clean) – 9 Points

3.      SI1 – Slightly Included (Clean) – 8 Points

4.      SI2 – Slightly Included 2 (Near Clean) – 7 Points

5.      I1 – Included (Un Clean) – 5 Points

6.      I2 – Included 2 (Flawed) – 3 Points

7.      I3 – Included 3 (Heavily Flawed) – 1 Points

 

·         Color Intensity (7) - CI

1.      Colorless (<10%) – 4 Points

2.      Pale (10%-15%) – 2 Points

3.      Light (15%-30%) – 6 Points

4.      Medium Light (30%-45%) – 7 Points

5.      Medium (45%-65%) – 5 Points

6.      Medium Dark (65%-85%) – 3 Points

7.      Dark (85%-100%) – 1 Points

 

·         Color Spread (3) - CS

1.      Even Color – 3 Points

2.      Non-Even Color – 1 Points

3.      Multi-Color – 2 Points

 

·         Cut & Polish (5) - CP

1.      Excellent – Symmetrical Cut and Clean Surface – 5 Points

2.      Very Good – Symmetrical Cut and Fairly Clean Surface  – 4 Points

3.      Good – Minor Asymmetry and Visible Surface Scratches – 3 Points

4.      Fair – Minor Asymmetry and Unclean Surface – 2 Points

5.      Poor – Asymmetrical and Flawed Surface – 1 Points

 

·         Luster & Brilliance (5) - LB

1.      Excellent – 5 Points

2.      Fine – 4 Points

3.      Good – 3 Points

4.      Fair – 2 Points

5.      Poor – 1 Points

 

 

 

Sample Gem Grading

 

Sample 1 - #SAPBLU0001

 

Stone Clarity: SC=9 Points

Color Intensity: CI=6 Points

Color Spread: CS=1 Point

Cut & Polish: CP=3 Points

Luster & Brilliance: LB=4 Points

 

GGS Score = SC*(CI+CS)*(CP+LB) =9*(6+1)*(3+4) = 9*7*7 = 441 out of 1000

 



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