Cut grading classification across diamond shapes
Currently most laboratories only provide cut grading for round diamonds as it is harder to assess the ideal proportions for fancy shape diamonds. The only laboratory that currently provides cut grades for fancy shaped diamonds is the less well known AGS, which introduced a Princess cut grade in 2005 and an Emerald cut grade in late 2006.
Based on existing values for the round brilliant and extensive research, Seventy Seven Diamonds has devised a table of recommended proportions for fancy shapes below. Please note these values are only to be used as a reference or guideline. We have grouped the shapes according to their cut classification type (brilliant, modified brilliant, step and mixed cut).