About Carat

A carat is a unit of measurement, used to weigh up precious gemstones including diamonds. In metric scale, a Carat is equivalent to 200 milligrams. Since 1907, a carat or metric carat has been adopted as a standard of measurement for gems in the United States followed by all other countries around the world.

The weight of smaller diamond is expressed in terms of ‘points’ which is numerically equal to .01 carat. In other words, one carat weight of diamond is same as 100 points. Therefore, if we say a diamond of .50 carat, we mean 50 points or 100 milligrams. Similarly, a 3 carat diamond would weigh 300 points or 600 milligrams.

Either the carat weight (abbreviated as ct) or the carat total weight (abbreviated as ctTW) is used to measure a diamond. It is one of the crucial indicators of diamond characteristics, popularly known as the Four Cs. In addition, the carat weight is a universally accepted measure for evaluating the quality of a diamond and further its price.

However, a carat weight does not indicate anything about the size of a diamond. It is observed that equal weight Diamonds do not necessarily have same sizes. The weight of a diamond is actually determined by its density and not by its diameter size. Therefore, a diamond with smaller diameter may weigh same as a diamond with larger diameter. Again, with a thinner profile a diamond can obtain a larger diameter size while the weight may remain same. Thus, interpreting carat weight in terms diameter size for a diamond does not hold good.

The price of a diamond is fixed depending upon the carat weight as well as the size of it. But the size of a diamond rather than its weight has a greater impact in determining the price. In addition, to judge the accurate Diamond pricing one should know other important factors or grades including the depth percentage, girdle thickness, symmetry, table percentage, polish, inclusions, culets and more.

It is further observed that diamonds having fractional weights (i.e. less than a full carat weight) are usually less expensive than diamonds with full carat weights. For example, a single diamond weighing 4 carats would be worth more than a set of tiny diamonds with a total weight of 4 carats. Therefore, it is more practical to consider the price per carat while comparing the values of similar but smaller diamonds.

Keeping other factors unchanged, a loose and uncounted diamond would demand more price than a jewelry piece with multiple diamonds setting.