N through R color graded diamonds are very light yellow. Diamonds S through Z have an obvious yellow tint. A diamond with more color than Z would be considered a fancy yellow diamond. Other fancy colors can occur, such as pink, blue, green, red, purple and orange. The third C of diamond grading is clarity, which refers to the diamond's natural characteristics, or inclusions, and blemishes.
Inclusions are internal while blemishes occur on the surface of the diamond.
The vast majority of diamonds have inclusions and blemishes. The size, number, position, nature and color or relief of these characteristics determine the clarity grade. Diamonds are graded under standard ten power magnification. A flawless diamond is the most rare and the most valuable. I 2 I 3 Flawless , Internally flawless very, very slightly included very slightly included slightly included imperfect Carat The Fourth C of diamond grading is carat.