The quality of a diamond’s cut is widely considered the most important of the 4-C’s in determining the beauty of a loose diamond; indeed, it is commonly acknowledged that a
well-cut loose diamond can appear to be of greater
carat weight,and have clarity and colour appear to be of better grade than they actually are. The skill with which it is cut determines its ability to reflect and refract light.
Proportion / Cut Grade: There are mathematical guidelines for the angles and length ratios at which the loose diamond is supposed to be cut in order to reflect the maximum amount of light.
Round Brilliant, the most common shape, are guided by these specific guidelines.
Fancy Shape stones are not able to be as accurately guided by mathematical specifics and aren’t graded on their cut or proportions, (only their finish or, polish and symmetry). Although cutting proportions aren’t graded in fancy shapes, there are examples when cut properly that will perform as brightly and beautifully as an ideally cut Round Brilliant.
Polish Grade: Describes how well the facets have been polished when finishing the diamond. An excellent polish enables light to enter and exit the
diamond crystal in the most efficient manner. Just like a window, if it isn’t well polished, the light passage will be interrupted. So, it’s true you could have the most ideal proportions for your stone but, if it isn’t highly polished, its full visual potential will never be seen!
Symmetry Grade: Analyses the size and alignment of the Crown (top) and Pavillion (bottom) facets, which determine the evenness of light return and scintillation. Please read on in our
diamond buying guide to discover how these technical terms impact on the real, visual qualities of the stone.
