Diamond clarity grading has some very specific measurements.  Simply put, analyze the nature and number of the inclusions in the diamond.  NATURE:  If the inclusion is large or small, breaks the surface or is internal.  Is it black or white, in the center or out to the side.  How noticeable is the inclusion?  NUMBER:  Are there several inclusions or a few?

When viewing a diamond to the naked eye or through a 10X loupe it is best to use a spiral motion with your eye slowing circling toward the center to find the inclusions.

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