A diamond’s “cut” actually refers to its proportions, symmetry and polish, and not the shape of the diamond as many are often led to believe. Deciding on the quality of a cut is extremely difficult to analyse and quantify without the assistance of a trained professional. This makes a diamond’s cut a vital aspect when considering a stone’s final beauty and value. One of the most important things when determining a diamond’s cut is how effective its facets are at interacting with light. Fire (which refers to the rainbow spectrum caused by the dispersion of light radiating from a diamond) and scintillation (the flashes of light or “sparkle”) are two additional primary effects on a cut’s appearance. The GIA Diamond Cut Scale is the standard for determining the cut grade of a round diamond. Fancy shape diamonds are not given an overall cut grading, however GIA does provide a symmetry and polish grading for all diamond shapes.

GIA Diamond Cut Scale


Choosing A Cut

  • We believe that cutImage_DiamondSelection_Cut_2 grade is the most important factor in determining the overall appearance of a diamond, if the grade of the diamond’s cut is poor the stone can appear lacklustre, irrespective of whether it possesses excellent colour and/or clarity.
  • For superior brilliance, choose a diamond with a cut grade of at least “very good” or “excellent” for round diamonds.
  • We would advise avoiding poorly cut diamonds due to their lifeless nature and we do not utilise poor diamonds in any of our pieces sold at the Matthew Ely boutique.