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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.

 

 
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