The Weight or Carat of a Diamond

The Basics
The weight or carat of a diamond is one of the fundamental attributes (one of the 4 C's) to knowing how to judge a diamond. A diamonds weight is measured in carats and one carat is equal to 0.2 grams. The weight or carat of a diamond has a significant impact on the size and therefore the value of a diamond. There are a few important points to remember:
  • A diamond that weighs twice as much does not necessarily look twice as big; the relationship is not 1:1
  • Larger diamonds are found much less frequently in nature. Because of this fact, a diamond that is 1.00 carat may be as much as 4x more in value than a 0.50 carat diamond; the relationship is almost exponential.
  • A mistake commonly made is to assume that carat is somehow related to the word karat used to describe the purity of Gold. Carat actually comes from the carob seeds which were used in ancient times to balance scales.

    Classification of Weight
    Diamonds are graded according to their polished weight i.e. the actual stone that you buy. The range of grading starts from just above zero and can be as much as 407.48 carats (the Incomparable Diamond, which is one of the largest diamonds in the world).

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    Words of Advice
    Choosing the best diamond is very much an individual choice. The best practice is to balance the weight with the quality of the stone.

    Achieving a larger size - If there is a limited budget and the size of the diamond is of the utmost importance, then slightly lowering the colour and clarity can help achieve the desired diamond size while remaining within the budget.

    Should you prefer a diamond with a different weight or carat than the choice offered on the website, please contact Customer Services.