The beauty of a cut diamond is in its incredible optical properties, in particular the way it bends light, and its play of color. The round brilliant displays of these properties show how all the factors blend in optical harmony with one another to create the highest degree of brilliance.

Color and Clarity are rarity factors given to us by nature. As the cut reveals these qualities, it also serves as a beautifying factor, which is enhanced by mans skill. The judgment of cut is based on the impression gained at first sight, in which beauty and brilliance are judged purely on personal standards. Thereafter, attention must be directed to the proportions of the cut stone. Here, facet angles and proportions must be tested for accuracy. The grading of the quality of the cut is therefore always made up of two components: a subjective opinion of the brilliance effect, and an objective judgment determined by checking the craftsmanship and measuring the proportions. In contrast, to color and clarity grading, where a natural degree of rarity exists, in cut grading it is the manual skill of the stone cutter which is judged, because it has a direct influence on how beautiful the stone is.