Symmetry Equals Light Performance

How Round Cut, Princess Cut and Square Cushion Diamonds Affect Light Performance?

We humans are always looking for that exceptional standard of perfection – particularly in our choice of a diamond.

Symmetry often equates with perfect beauty, so it is not surprising that Round Cut, Princess Cut and Square Cushion Cut diamonds are favored choices - but it is their light performance that places them in a category of their own. The symmetry of a diamond refers to the arrangement, size and shape of its facets. Simply put, it is the mastery of perfect symmetry and cut which affects the degree to which the diamond interacts with light. The more perfect and symmetrical the cut, the more precise the diamond’s light interaction and the higher its light performance will be.

A well-cut, symmetrical diamond allows the light to travel through as it bounces off the stone’s facets and angles and back to your eyes. That’s the ultimate excitement factor when considering a diamond purchase; it’s the interplay and intensity of light that is pure magic. However, a badly cut stone with poor symmetry, an off-center culet, wavy girdle or misplaced table sends light though defective angles through the bottom or sides - and not back to the eye - making the diamond look dull, ordinary and unexciting.

In a symmetrical diamond the scintillation, fire and brilliance are sheer perfection. Scintillation or sparkle is thrown off when the light shimmers from facet to facet towards the center of the diamond as it is moved in the light. Your diamond literally looks as if it is dancing in the light. Fire is the spectacular effect produced when white light disperses into colors of the rainbow as it hits the diamond’s facets. Brilliance is the dazzling effect when the diamond reflects the stone’s white light return.

 The Round Brilliant Cut diamond offers exceptional light performance. It features 58 facets, including the culet, which allow the light to enter the diamond, reflect off every facet, and bounce back to the eye to create that glamorous, unmistakable, optimal sparkle. It was developed in 1919 by Marcel Tolkowsky and remains by far the world’s most popular diamond cut.

The Princess Cut is square, with a length to width ratio of 1.0 -1.05 and between 50 and 58 facets. It is the most brilliant of the square-shaped diamonds, though its light performance doesn’t quite measure up to the dazzling Round Cut. The Princess features from two to four chevron patterns, which can be viewed from above. If the diamond has two chevron shapes it reflects bolder flashes of white; with four chevrons the stone has more scintillation.

Square Cushion Cut diamonds have rounded edges, similar to the shape of a pillow - hence their name – and they have from 58-64 facets. They have a length-to-width ratio of 1.00 -1.05, and they are the cut with most dispersion or flashes of fire. Cushion Cut diamonds with precision-cut Hearts and Arrows offer superior light performance, so they are often preferred. Hearts and Arrows cut diamonds have exact angles and symmetry, and they show a pattern when viewed with special equipment; arrows are visible from the top, and hearts are visible when the diamond is face-down.

We all look for harmony in our lives. Most art forms consider symmetry as the expression of pure perfection and as the classic standard of beauty. A symmetrical diamond is in a league of its own.