The GIA Cut scale levels are: Excellent, Very Good, Good, Fair and Poor. The GIA Cut grade assesses the diamonds in these primary ways:
Face-Up Appearance is the most important part of GIA’s cut grade assessment.
Brightness: Usually referring to the “brilliance” of a stone.
Fire: Display of colored light return as observed in stronger lighting conditions.
Scintillation: Movement of the light’s pattern within the diamond as the diamond observer or light source is moved.