How well a diamond is cut has a lot to do with the stone's fire and brilliance. Brilliance describes the reflections of white light coming from the diamond. A diamond that is cut either too shallow or too deep will not be as brilliant as a properly cut diamond. Cut should not be confused with shape. To learn about diamond shapes, see above.
Diamonds are graded according to the GIA color chart. The letters D through Z are used to designate a diamond's color with D being colorless and Z-graded stones having a lot of color. Most often thought of as a colorless stone, diamonds also come in a rainbow of fancy colors. Fancy diamonds are very rare, valuable and sought after by collectors.
Color Rating Chart
CARAT WEIGHT
A very accurate unit of weight used for gemstones. The word Carat is derived from the Carob seed, which was used in the days of antiquity as counterweights on scales for small measurements because Carob seeds were extremely similar in weight. The weight of a diamond is measured in carats. Total carat weight (T.W.) is the total weight of all the stones in a piece of jewelry. One carat is equal to 100 points. The term carats is often confused with "Karats". "Karat" is a measurement of gold purity and has no relationship to the term Carats. The price per carat rises dramatically as the diamond increases in size, simply because larger diamonds are rarer, and found less frequently. Diamonds of the same carat weight vary widely in price, because of other factors that include clarity, cutting or proportion, and color.
