Diamond weight
- Carat refers to a diamond´s weight, however, it does not necessarily reflect a diamond´s size
- Carat weight is highly influenced by the diamond´s cut and shape
Carat represents the weight of a diamond. One carat weighs 0.2 grams and therefore one gram equals a 5 carat diamond. The word originates from the carob trees´seeds that were used in ancient times as weight measurement units due to their assumed uniformity. In the trade one carat is divided into 100 points which means 0.25 carat diamond is also called a 25-points-diamond.
Even though most people relate carat weight to diamonds, it is important to stress the difference between a diamond´s weight and its size: Just like a person´s weight does not necessarily correlate with the height, the mere carat weight does not accurately describe the size of the diamond. In fct, the diameter and cut determine the size of a diamond to a great deal. Consider the following illustrations
“Shallow” diamond vs. “Deep” diamond
While one diamond has a bigger diameter and appears larger looking from above, the other retains most of its weight in the pavilion, the lower part of the stone, and therefore seems smaller even though they both have the same weight. Usually a “flat” and seemingly bigger diamond compromises on cut and therefore is lacking brilliance and fire. The same is true for “heavy” diamonds with large pavilion depths.
A 1.00 carat diamond can have a diameter in between approximately 5.75 mm to about 6.9 mm. Most round brilliants with cut grade “excellent” are in between 6.3 mm to 6.6 mm in diameter and most people consider a diameter of 6.4 mm to 6.5 mm most desirable.
We recommend you to always take the cut in consideration when choosing a diamond. If you have further questions on this topic our experts will gladly help you.
| Measuring a diamond´s diameter with a gemstone gauge | This is the fruit of a carub tree whose seeds were believed to be identical in weight |
 |  |