Diamond Education To establish a diamond's quality and value, jewelers examine each of the 4 C’s: cut, clarity, carat weight, and color. The combination of the 4 C’s determines the value of a particular diamond. The finest stones possess the rarest quality in each of the 4 C’s and are the most valuable. Cut A well cut or faceted diamond, regardless of its shape, offers the greatest brilliance and value. While nature determines a diamond's clarity, carat weight and color, the hand of a master craftsman is necessary to release its sparkle and beauty. When a diamond is cut to good proportions, light will reflect from one mirror-like facet to another and disperse through the top of the stone. Diamonds that are cut too deep or too shallow lose light that spills through the side or bottom. As a result, poorly cut stones will be not be as brilliant, and thereby less beautiful and valuable than well cut diamonds. Clarity The greater a diamond's clarity, the more brilliant, valuable and rare it is. All natural diamonds contain identifying characteristics that can be seen under the scrutiny of a jeweler's magnifying loupe, which are called inclusions. These are nature's birthmarks, and they may look like tiny crystals, clouds or feathers. Diamonds categorized as internally flawless reveal no such inclusions. Flawless stones are treasured for their rarity and beauty. The number, color, type, size and position of surface and internal markings affect a diamond's value. Major inclusions can interfere with the path of light that travels through a diamond, diminishing its brilliance and sparkle and therefore its value. Carat Carat is the measurement of a diamond’s weight. What makes a bigger diamond desirable is that it shows off a stone's fine color and cut, and therefore its brilliance. While larger diamonds are highly prized, diamonds of equal size may vary widely in value and brilliance, depending on their qualities of clarity, cut and color. Color Diamonds are graded by color, starting at D and continuing through the alphabet. Truly colorless stones, graded D, are treasured for their rarity and value. While many diamonds appear colorless, they may actually have subtle yellow or brown tones. Although still beautiful, they will be less rare and therefore less valuable. "Fancy" diamonds, which can be red, pink, blue, green and canary yellow are highly prized and particularly rare.