F clarity

F means flawless: no marks inside or on the surface, even at 10x magnification.

Grade: 1st of 11, the best
In nature: So rare that many jewellers go a lifetime without seeing one.
In RXXO: 1 in 330 diamonds

F in RXXO

12diamonds like this in RXXO right now

Questions

What does F mean on a diamond?

Flawless. No marks inside or on the surface, even at 10x magnification.

How rare is an F diamond in RXXO?

About 1 in 330. Together, F and IF are about 1 in 170.

Is F better than IF?

Yes, by one grade. F sits just above IF on the 11-step clarity scale. In RXXO, an F is about 1 in 330, an IF about 1 in 330.

RXXO numbers are the odds every mint draws from. Updated 8 October 2026.