Much is made and written of a diamond's clarity, but of the Famous 4 Cs, it is the easiest to understand. According to many experts, generally has the least -of all other Cs- impact on a diamond's appearance. Clarity simply refers to the tiny, natural imperfections that occur in all but the finest (Flawless) diamonds. Gemologists refer to these imperfections by a variety of technical names, including blemishes, inclusions, crystals, twinning wisps and others. Diamonds with the least and smallest imperfections receive the highest clarity grades. Because these imperfections tend to be microscopic, they do not generally affect a diamond's beauty in any discernible way.