Diamond clarity refers to internal and external characteristics in a diamond, commonly known as inclusions and blemishes. An inclusion is an internal or external characteristic or flaw that occurs during the Earth's natural process of diamond formation and can affect the diamond's overall appearance and value. Most diamonds contain inclusions that are not visible to the naked eye.

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The Gemological Institute of America (GIA), one of the most reputable gemological laboratories, has established a standard grading scale for diamond clarity ranging from Flawless to Included. This clarity scale measures the amount and locations of inclusions in a diamond. The fewer inclusions and blemishes a diamond has, the higher its clarity grade is based on the GIA diamond clarity scale.