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Northwest Gemological Institute

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Diamond Grading                                 workshop series

Length: 16 hours
Instructor: Ted Irwin, Graduate Gemologist
                NGI Director

Our most popular course shows why diamonds are in a class by themselves.

Identify inclusions by dark-field binocular microscopic examination, then diagram those characteristics for identification and apply the clarity grading standards of the G.I.A. (Gemological Institute of America).   Learn to properly use a jeweler's loupe for diamond inspection and presentation. Use proven methods to reliably estimate carat weight of loose and mounted stones.

The principles of color grading with "master" comparison sets will be covered as well as the parameters for the "champagne" color series and fancies.

Cutting procedures, styles and proportion analysis of the AGS (American Gem Society) and the new GIA system will demonstrate the importance of proper cut and its impact on both beauty and value.

Students examine diamond treatments, such as fracture-filling and learn to identify popular substitutes such as Cubic Zirconia and synthetic Moissanite as well as synthetic diamonds.

Our laboratory workbook covering the course topics and grading scenarios is the student's to keep for future reference.

 

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