carat

     The weight of a diamond is generally given in carats. One carat equals 0.2 grams. The weight of small diamonds is frequently expressed in points, with one point equaling 0.01 carats.
     Diamonds that look big for their weight may have reduced brilliance and fire. An increase in carat weight does not produce the same increase in millimeter diameter. For example, there is a 25% increase in weight from 1.00 carats to 1.25 carats but less than 8% increase in diameter (6.5 to 7.0 mm).
      Look for diamonds that have a diameter measurement that is at least as large as the average for that weight. There is no need to pay for the weight you can't see.

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