Diamond Guide

Diamond Carat Weight

The Diamonds weight is measured in carats — a term not to be confused with karats, which indicate the purity of gold (e.g. 18K = 75% gold).

A carat is a unit of weight where 1 carat equals 0.2 grams. For example, 0.50 carat equals 0.1 gram, and 5 carats equal 1 gram.

As the carat weight of a diamond increases, so does its size. However, this relationship is not linear but rather curved, meaning a 2.0 carat diamond will not appear twice as large as a 1.0 carat diamond, as illustrated above.

This is also true for other diamond shapes. Have a look at the square shaped diamond below.

Moregola's Expert Tip

Specific diamond sizes, such as 0.50 carat, 0.75 carat, and 1.0 carat, are particularly popular, and prices can fluctuate significantly based on carat weight. For instance, a 0.90 carat diamond may offer 10-20% better value compared to a 1.0 carat diamond of the same quality. Though they may look nearly identical in size, their prices can be markedly different.

While carat weight gives an idea of a diamond's size, the stone's shape and cut are crucial in determining how large it appears. For instance, an elongated shape like the Marquise cut might seem larger than a round shape like the round brilliant, even if both stones have the same weight. For a more detailed exploration of diamond shapes, please click here.

When comparing diamonds of the same shape, it's important to consider the cut grades and the proportions of the table and depth, as shallower diamonds will generally look larger than deeper ones. Other factors, like the width of the girdle, can also influence how big a stone appears without necessarily impacting the stone’s quality. To delve deeper into diamond cuts, please click here.