Diamond Sizes

Wondering how to measure a diamond’s size?

Though diamonds are measured by weight (carat)- when we plan the jewelry design and the setting of the diamond, we must measure the diamond’s diameter in millimeter. For example, in order to plan a tennis bracelet with diamonds that each weigh 0.10 carat (which are “10 points”), there must be a preparation for placing the three-millimeter diameter diamonds. Since these are round diamonds, an identical diameter of the diamonds will promise an identical weight of the diamonds. We are often asked what the diameter of a half carat diamond is or what the diameter of a 0.70 carat may be. The following table includes the average sizing of round diamonds.



Here’s a little exercise to make sure this is clear…

Take a look at the table and see if you can find the average diameter of a round diamond weighing half a carat.