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Diamond Carats

A diamond’s weight is determined by carat. Carat weight, an objective metric, is the most widely used method of determining a diamond’s size.

Diamond Carats Scale by Measurement

The carat weight of a diamond determines how big it is. Up to two thirds of the total carat weight may be lost when raw diamonds are cut and polished into finished diamonds. A single two carat diamond will cost more than two one-carat diamonds of the same grade because larger rough stones of good quality are harder to find than smaller rough gems of similar quality.

A diamond’s weight will rise considerably more quickly than its actual “face-up” diameter. For instance, whereas the width of an excellent cut one carat diamond is around 6.5mm, a diamond that is twice as heavy is just 8.2mm wide, or less than a 30% increase. The diagram above makes this concept more clear.

Difference between CT and CTW

  • CT refers to carat weight of the single diamond (center stone in most cases) and CTW or CTTW refers to the total carat weight of all diamonds mounted in a single piece of jewelry.
  • PT refers to “point” which is 1/100th of a carat. For example “5pt each” means that the each diamond in that piece of jewelry is at least 0.05 carat weight.


Helpful Tips:

  • Carat refers to diamond’s weight and not its size
  • Bigger diamonds does not mean extra sparkle. Cut plays major part maximizing the sparkle and brightness of the diamond. Blingster only use “Very Good” or “Excellent” cut diamonds for any piece of jewelry scaled on GIA cut standards.

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