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Diamond Polish

What Is Diamond Polish?

The way light passes through diamonds is influenced by the polish. A diamond’s overall brilliance is dependent on this important attribute. It is best to choose diamonds that are certified by laboratories with good, very good or excellent polish. The diamonds that are significantly less brilliant have poor polish because the surface of the stone is blurred by microscopic polish lines, thus reducing the amount of light that enters or exits the diamond. Because some diamond cutters want to reduce their costs, they don’t spend sufficient time to properly polish a diamond, thus resulting in a poor polish.

How Is Polish Graded?

Polish and symmetry are similarly graded. GIA, AGS and IGI reports grade polish as Excellent, Very Good, Good, Fair or Poor but AGS and IGI also added Ideal to their list.

  • (EX or E) - Excellent polished diamonds are the ones that appear flawless at 10 x magnification.
  • (VG or VGD) - Very Good polished diamonds are polishes with lines extremely difficult cu locate under 10 x magnification.
  • (GD, GO, G) - Good polished diamonds are polishes with lines difficult to see under 10 x maginification.
  • (F, FR, FA) - Fairly polishes have lines noticeable under 10 x maginification.
  • (PR, PO, P) - Easy to see under 10 x maginification of visible with the unaided eye lines make the polish to be graded as Poor .
  • (VP, VE) - Very poor polishes present lines easy to see with the naked eye.
  • (EX or EP) -  Lines that are obvious with the naked eye put polishes in the Extremely Poor category of grading.

The naked eyes see very little difference between these ratings. A polish rating of Good can still mean the stone is remarkable. The differences are only noticeable under magnification. However, flaws that are visible to the naked eye affect the overall beauty of the diamond and put the diamond in the Fair (FR) and Poor (PR) category.