The easiest way to determine the weight of a gemstone is to measure its diameter
- Both the stone’s measurements and carat weight are listed on a gemstone certificate.
Gemstone Size: Different Gemstone Densities Effect the Weight
The size of a gemstone is not merely determined by carat weight. For a more accurate estimation of a gemstone’s size, measure its diameter from the top view.
The main reason why comparing gemstone weights is difficult is because of the different densities of gemstones. For example, when comparing the size of a ruby and a diamond, the ruby will appear much smaller in size though both stones weigh the same. This is because ruby is denser than diamond. Make sure to check the diameter when you buy any gemstone.