The Grade-Maker (6.49)
The grade-maker is the principal inclusion that causes a grade to fall into its predestined category. A large white feather accompanied by many tiny white crystals is a good example. If all the tiny white crystals were taken away, the diamond would still be the same clarity grade, since the grade-maker is the large white feather. The grade-maker dominates the accompanying inclusions by its size and/or contrast, and possibly by its location.
A grade-maker could still be defined as many small inclusions, but in this case, the term would not be used as readily since there wouldn’t be a main inclusion that dominates the final clarity grade.