ADVANCED DIAMOND FILTERS
Although not so often referred to, a diamond's fluorescence has an impact on it's transparency. Some diamonds may appear brown, hazy or milky, even to the naked eye. This is because they have a very high level of fluorescence. However, a moderate element of fluorescence does not tend to effect the sparkle of the diamond. In the case of smaller size stones and lower grade colours, such as I and J, a certain degree of fluorescence can lend the stone a more colouless or white appearance.
When the facets of a diamond are well balanced and aligned, the stone has symmetry, which is critical to creating optimal brilliance and scintillation. Errors in symmetry include facets that are not properly aligned, improperly shaped facets, or an off-centre table reduce brilliance
After a diamond is cut, each facet must be polished. The process can leave surface scratches or marks. If a diamond has no scratches or very minor ones, the polish is of a high degree. Scratches, lines, burn marks created by excessive heat, or rough girdles could downgrade the polish rating of a diamond.