Modified Brilliant Cut

• Introduction
• Round Brilliant Cut
• Modified Brilliant Cuts
• Step Cuts
• Mixed Cuts
• Vintage Cuts

Modified Brilliant Cuts

Any style of diamond cutting other than the round brilliant or single cut is called a fancy cut, or fancy shape. The cuts that have been developed based on the original round brilliant design are known as modified brilliant cuts. Modified brilliants include the Princess, Marquise, Oval, Pear, Heart and Trilliant cuts.

Princess Cut

The ideal proportions of table and depth are much higher for a Princess than for a round brilliant cut. On a GIA certificate, the technical name for a Princess cut is a modified square- or rectangular brilliant cut. It can have the same number of facets as a round diamond (57), but may have as many as 76 or even up to 144.

To read more about the round princess cut, please click here.

Beyond the most popular Princess cut, Modified Brilliants come in a range of other shapes. The Radiant cut, which can be square or rectangular usually comes with 70 facets, whilst the Oval (which is in effect an elongated round) often has 58 facets. Other shapes include a tip formation such as the Pear shape (56-58 facets), Heart Shape (usually 56-58 facets), and Marquise (56-58 facets).

Other factors to take into account for Modified Brilliant Cuts include:

Bow tie effect: Some fancy shape diamonds have two black triangles across the middle of the diamond that look like a bow tie. Although bow ties are normal in some fancy shapes, a bow tiethat is too big diminishes a diamond's beauty. Depending on the size, angle and placement of the diamond's facets, this bow tie can be barely visible (‘minimal’) or very pronounced. It occurs from the variations in the pavilion facet angles which are longer than they are wide which results in a small amount of light leaking through the diamond. Facets are suppose to alternate between light and dark as the diamond, viewer or light source are moved but with the bow tie effect, certain facets stay relatively dark regardless of the movement.

Girdle Thickness: Girdle width varies considerably more in fancy shapes than in the round brilliant. For example, the marquise, pear and heart cuts shapes tend to have thick girdles or are extremely thick at the tips, or in the cleft of the heartshape. The princess cut, on the other hand, which has square corners, may have an extremely thin girdle. It is generally recommended to avoid extremely thin or thick girdles to avoid chipping at one extreme and retaining excessive weight to the detriment of the size of the diamond.

Further Reading

• Anatomy of a Diamond and the effects of light
• Cut Grading
• Polishing (Cut) Process
• Hearts and Arrows