What is a radiant cut diamond?
By Jared James · Last updated 21 May 2026
Definition
The radiant cut is a rectangular or square diamond with cropped corners and brilliant-style faceting on both its crown and pavilion, giving it intense sparkle in a rectangular form. It was created by Henry Grossbard in 1977 and was the first rectangular cut to use full brilliant faceting throughout, combining the clean geometric outline of the emerald cut with the fire and brightness of a round brilliant. Radiant cuts are an excellent choice for coloured diamonds because the faceting pattern maximises colour richness as well as sparkle.
Frequently asked questions
- Is a radiant cut the same as an emerald cut?
- Both are rectangular with trimmed corners, but they are quite different in appearance. An emerald cut has step facets that create a calm, hall-of-mirrors effect, while a radiant cut has brilliant facets that produce much more sparkle and fire. The radiant is considerably more active visually.
- Do radiant cut diamonds show inclusions easily?
- Brilliant faceting, as in the radiant cut, tends to mask inclusions better than step cuts because the sparkle distracts the eye. This means you can often choose a slightly lower clarity grade in a radiant cut and still have a clean-looking stone.
- What ratio is best for a radiant cut diamond?
- A square radiant cut is around 1.00 to 1.05 length-to-width ratio. For an elongated look, most people prefer somewhere between 1.20 and 1.35, which gives a rectangular shape without looking too narrow. Personal preference varies, and elongated radiant cuts have grown particularly popular in recent years.
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