{0} days til christmas


Carat Weight And Size

How are sapphires measured?

Gems vary in density, so a sapphire and a diamond of the same carat weight are visually different sizes. Because sapphires tend to be heavier, a one carat sapphire is generally slightly smaller in size than a one carat diamond. For ease of selection and setting, size is a more useful measurement, which we list in millimeters (mm). Our standard size for a round sapphire is 6 mm, which is approximately one carat.

Brilliant Earth carries a variety of shapes and sizes beyond our standard so if you are looking for something more unique, please contact us.



Share our story with others

know moreabout the issues
  • 15 Amazing Facts about Diamonds
    15 Amazing Facts about Diamonds

    Diamonds are the birthstone for the month of April, meaning that April-born ladies have an extra reason to ask for gifts of sparkling... Read More

  • 10 Reasons to Celebrate on Our 10th Anniversary
    10 Reasons to Celebrate on Our 10th Anniversary

    We’re celebrating a special occasion this week. Ten years have passed since our co-founders, Beth and Eric, teamed up to launch Brilliant Earth. Our... Read More