Diamond Shapes Guide

Shape is not cut

Shape is the outline of a diamond seen from above. Cut is how well its facets are proportioned and polished, explained in the diamond 4Cs guide. Shapes fall into two families: brilliant cuts, with many triangular and kite-shaped facets that sparkle, and step cuts, with long rectangular facets that create broad flashes of light.

Round

The round brilliant is the most popular shape and usually returns the most sparkle. Because cutting a round wastes the most rough diamond, rounds tend to cost more per carat than other shapes.

Oval, pear, and marquise

These elongated brilliant shapes look larger than a round of the same weight and lengthen the finger. Many show a darker band across the middle called a bow-tie, which varies stone to stone. The points of pears and marquises are best protected by a V-shaped prong.

Princess, cushion, and radiant

The princess is square with sharp corners, which should be protected by prongs. The cushion is square or rectangular with rounded corners and a soft, vintage feel. The radiant combines a rectangular outline with brilliant faceting for strong sparkle.

Emerald and Asscher

These step cuts have a clear, mirror-like look. Their open facets show inclusions and color more readily, so a higher clarity grade is worth more in these shapes than in brilliant cuts.

Heart

The heart is a romantic brilliant shape. It needs good symmetry to read clearly, and small hearts can look like a triangle once set, so it shows best at larger sizes.

Common questions

Which diamond shape looks biggest for its carat weight?

Elongated shapes such as marquise, oval, and pear usually look larger face-up than a round of the same weight.

Which diamond shape sparkles the most?

The round brilliant, followed by other brilliant cuts such as oval, cushion, and radiant.

Which shapes need protective prongs?

Shapes with points or sharp corners, such as princess, pear, marquise, and heart, benefit from prongs that cover the corners or tips.