5.1 Weight

5.1. WEIGHT

The weight of a diamond is always expressed in carats (ct), up to two decimals at least.
Is the weight expressed up to two decimals only, then it is rounded off downwards if the last three decimals are smaller than 849 (< x.xx849 ct). When the last three decimals are higher than 850 (> x.xx850 ct), the weight is rounded off upwards. (Reference norm: NEN 1047)

0.99850 ct  0.999 ct  1.00 ct
0.99849 ct  0.998 ct  0.99 ct