Diamond Polish

What Is Diamond Polish?

Diamond polish refers to the smoothness of a diamond's surface and plays a crucial role in its brilliance. It determines how well light travels through and reflects off the diamond. When choosing a diamond, it's best to select one with a laboratory certification that rates its polish as Good, Very Good, or Excellent. Diamonds with poor polish tend to have microscopic lines on their surface that blur its clarity, significantly reducing brilliance. These imperfections also limit the amount of light that can enter or exit the diamond. It's important to be cautious, as some diamond cutters may reduce their costs by spending less time on polishing, leading to poor polish.

How Is Polish Graded?

Polish is graded in the same manner as symmetry, with five possible ratings: Excellent, Very Good, Good, Fair, and Poor. These ratings are provided on reports from major gemological institutes like GIA, AGS, and IGI, with some institutes also offering an "Ideal" rating.

  • EX or E (Excellent): Flawless at 10x magnification

  • VG or VGD (Very Good): Extremely difficult to detect at 10x magnification

  • GD, GO, G (Good): Very difficult to see at 10x magnification

  • F, FR, FA (Fair): Noticeable under 10x magnification

  • PR, PO, P (Poor): Easy to see under 10x magnification, visible to the naked eye

  • VP, VE (Very Poor): Relatively easy to see with the naked eye

  • EX or EP (Extremely Poor): Obvious flaws visible without magnification

Although there is little visible difference between these ratings to the naked eye, diamonds rated Good can still be stunning. The variations become more apparent only under magnification. However, ratings of Fair (FR) and Poor (PR) indicate visible flaws that impact the diamond's overall beauty.

Other Considerations:

It’s also important to ensure that the metal of the ring is free from porosity or rough spots. Porosity refers to small holes in the metal surface, which deepen over time. These issues are typically caused by mass-producing rings with insufficient quality control. Porosity weakens the ring and is irreparable. A ring with porosity will eventually degrade and break.