Carat is a measurement of the a gems mass and weight, being roughly equal to one-fifth of a gram. The second aspect refers to hue and saturation; few people realize that certified diamonds come in an amazing variety of colors, ranging from white to bark brown and even black. Some colors, such as pink, are tremendously valuable. Clarity refers to any cloudy spots or apparent scratches visible within the gem; naturally, the less apparent these are, the better.

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