When comparing the clarity of a 3-carat Marquise diamond, cognizance on identifying any seen inclusions or blemishes in the stone. opt for a diamond with a clarity grade of VS1 (Very barely included) or better, as this ensures minimal flaws which might be hard to come across with out magnification. take note of the diamond's standard transparency and brilliance, warding off stones with sizeable imperfections that could affect the gem's sparkle.