What is a woman’s favorite type/cut of diamond?

The Round Brilliant is by far the most popular shape, and it is the most readily available in every possible quality and size.

Contrary to popular belief and perhaps your experience in most stores, fancy-shaped diamonds (as all non-round diamonds are called) are often less expensive than their round brethren... at the wholesale level.

The Princess cut is becoming popular because it is both brilliant and unique. The Princess shape actually saves money for a cutter, since it is closest to the octahedral "habit" of rough diamond crystal, the most common formation of diamond in the rough. (The octahedron is like two pyramids base to base.)

Compared to a Round Brilliant, a cutter can retain more of the original crystal when cutting an octahedron into a Princess shape. The square corners of the rough need to be cut away to create a Round, but they are saved when cutting a Princess.

The more he saves of his original rough crystal, the less the cutter loses on his financial investment in the stone, and therefore you pay less as well.

But many shapes can be beautiful if they are cut well, including the Marquise, Oval, Pear, Radiant, Heart, Emerald and other major shapes. But all fancy shapes have an inherent difference in the physics of light. The longer shapes have a slight "bow tie" effect. This means they have a small zone in the center where light leaks out the bottom, creating a darker area in the shape of a bow tie. This is especially true for the Pear, Oval, Marquise, and Heart shapes.

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