The diamond shows no inclusions or blemishes of any sort under 10X magnification when observed by an experienced grader. Note: Truly flawless or internally flawless (F or IF on the GIA’s grading scale) diamonds are extremely rare.
The diamond has no inclusions when examined by an experienced grader using 10X magnification, but will have some minor blemishes.
The diamond contains minute inclusions that are difficult even for experienced graders to see under 10X magnification.
The diamond contains minute inclusions such as small crystals, clouds or feathers when observed with effort under 10X magnification.
Inclusions are obvious under 10x magnification and may or may not be visible to the naked eye. However, when set in jewelry, the inclusions may become less visible.
Inclusions are obvious under 10x magnification and are usually visible to the naked eye. This quality allows for a larger diamond to be purchased at a lower price.