Most people consider the cost of diamonds somewhat mysterious. But really, it's not mysterious at all. The cost of diamonds depends upon four characteristics called the 4C's, although we at Curt Parker Jewelers teach you the 10C's of diamond buying. Clarity Most diamonds contain very tiny, natural birthmarks known as inclusions. However, the fewer and smaller the inclusions are, the less likely it is that they will interfere with passage of light through the diamond.
Clarity is rated in grades from flawless to imperfect.
Cut Don't confuse cut with shape. A well cut diamond is better able to return light, creating more fire, brilliance and sparkle. The most prized diamonds are colorless diamonds, because they are rare. The color grading scale varies from totally colorless to light color. The difference between one grade and its neighbor is very subtle.