How do we weigh diamonds?

Diamonds are weighed by very accurate electronic carat weights. The weight of the diamond can also be measured by measuring two dimensions - diameter (at least in two perpendicular axes) and height.

The weight of the diamond is given in carats (ct). In diamond certificates, you'll find the weight of the diamond accurate to 2 decimal places.

1 ct = 200 mg = 0.2g 1 g = 5 ct

Did you know that the most common weight of diamonds in sold jewelery is in hundredths, tenths or units of carats.

What are karats?

   Carat - weight of diamonds X Karat - gold fineness


Carat (ct) is a unit of weight used in jewellery for diamonds or pearls. At present, the so-called metric carat, which is exactly 200 mg (0.2 g), is used.


Karat (kt) is a dimensionless unit of grandeur of gold jewelery. The fineness of pure gold is defined as 24 kt.



Sources used: (2016). Diamond Quality Factors. [Online] Available at: [Accessed 6 Dec. 2016].