Polish influences how well light is able to pass through a diamond. It is a very important attribute in determining a diamond's overall brilliance. When choosing a diamond, it is best to pick one that is laboratory certified with good, very good or excellent polish.

Diamonds with poor polish are significantly less brilliant because they have microscopic polish lines that blur the surface of the stone. They also reduce the amount of light that enters or exits the diamond. Be aware that many diamond have a poor polish because diamond cutters try and reduce costs by not spending sufficient time to properly polish a diamond.

SGS Polish Grades Description
EX Excellent, Flawless at 10 power.
VG Very Good, Extremely difficult to locate under 10 power.
G Good, Very difficult to see under 10 power.
F Fair, Noticeable under 10 power.
P Poor, Easy to see under 10X / Visible to unaided eye.
VP Very Poor, Relatively easy to see with the unaided eye.
EP Extremely Poor, Obvious to see with unaided eye.