Diamonds are graded for certification by laboratories using grading criteria. Four of these criteria are critical to understand when making a diamond purchase or investment. Known as the “Four C’s” these criteria are: color, cut, clarity and carat.
Color is the result of the composition of a diamond and it does not change. When a jeweler is describing the color of a diamond they are referring to the presence or absence of color in white diamonds. Because a diamond with no color allows maximum light to pass through, colorless diamonds are preferred for their sparkle.
Carat is the unit of weight by which diamonds are measured. One carat is equal to 200 milligrams. A carat is divided into 100 segments called points. 150 points would equal one and a half carats.
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