A diamond's cost is based on the characteristics known as the "4 C's": Clarity, Color, Cut and Carat Weight.
Clarity
A diamond's clarity is determined by the number, nature, position, size and colour of internal characteristics called "inclusions" and surface features called "blemishes". The clarity scale ranges from flawless (FL), meaning a gemstone has no internal or external flaws, to severely included (I3), meaning there are many flaws clearly visible to the unaided eye.
Color
Color describes the amount of color the diamond contains. For diamonds, the complete color scale ranges from D, indicating no color at all, to Z, which indicates a distinct yellow-brown or grayish cast.
Cut
Cut refers to the proportions, finish, symmetry, and polish of the diamond. These factors determine the brilliance and sparkle of a diamond.
Diamond weight is measured in carats. There are 115 carats to an ounce. A carat can be divided into 100 equal parts called points, so a 50-point diamond is one half of a carat.
