Diamond polish

The way in which a diamond is polished influences how well light is able to pass through a diamond and its resulting level of brilliance. A diamond that is laboratory certified with good, very good or excellent polish should be selected. Diamonds that have poor to extremely poor polish are less brilliant as they have microscopic polish lines which blur the surface of the diamond. These microscopic lines reduce the amount of light that enters or exits a diamond thereby greatly reducing the brilliance.

Diamond reflection

Polish terminology as seen on grading certificates:

P = Poor

Prominent heavy polish features are seen face-up at 10 x magnification. The lustre of the diamond is significantly affected when viewed with the unaided eye.

F = Fair

Obvious heavy polish features are seen face-up at 10 x magnification. The lustre of the diamond is affected when viewed with the unaided eye.

G or GO or GD = Good

Noticeable polish features are seen face-up at 10 x magnification. The lustre of the diamond may be affected when viewed with the unaided eye.

VG or VE = Very Good

Minor polish features are seen face-up at 10 x magnification.

E or X or EX = Excellent

Ranges from no polish features to a few minute polish features that can be viewed with difficulty face-up at 10 x magnification.