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The CUT of a diamond includes considerations like symmetry, depth, crown and pavilion angles, uniformity of facets, quality of polish and the overall skill of the cutter that sculpted the stone. Most gemologists consider cut to be the most important diamond characteristic. A poor cut will dull the brilliance of a diamond of perfect colour and clarity.


Referring to the pattern of angled facets on the surface of the diamond, the cut of a diamond determines its brilliance and fire. People often confuse a diamond's cut with its shape. Shape refers to the physical form and contour of the diamond, whereas the quality of its cut dictates overall proportion and how it reacts to light. A diamond's sparkling character and reflective brilliance increases in proportion to the fineness of its cut.


Cutting a diamond to ideal proportions sometimes requires sacrificing up to half of the crystal's initial weight. Consequently, such diamonds are sold at a relatively higher per-carat price.


A note about brilliant-cut stones:

Brilliant-cut is a specific diamond cutting style developed to maximize a diamond's optical properties. A Brilliant-cut diamond can have several shapes: Round, Princess, Marquise, Radiant, Pear, Oval, Heart and Cushion. A Brilliant-cut diamond that is well cut, highly polished and well-balanced in proportion will give you that stunning fire, brilliance and sparkle you're looking for.


Key Points

  • Cut is a diamond's most important characteristic.
  • It has the greatest overall influence on a diamond's beauty.
  • It determines what we generally think of as sparkle.