Diamond Shape Guide
Radiant
The radiant cut blends the elegance of the emerald shape with the brilliance of the round — a versatile, high-fire option in a rectangular format.
70 facetsBrowse Radiant Diamonds
About the Radiant
Introduced by Henry Grossbard in 1977, the radiant cut was the first rectangular shape to feature a complete brilliant-cut facet pattern on both the crown and pavilion. This gives it the geometric silhouette of an emerald cut with the fire and brilliance of a round brilliant — truly the best of both worlds. The radiant is available in square and rectangular proportions, and its trimmed corners make it more durable than the sharp-cornered princess. It is an excellent choice for coloured diamonds, as the brilliant faceting intensifies body colour beautifully.
Characteristics
- Rectangular or square with trimmed corners
- Complete brilliant-cut facet pattern
- Exceptional fire and brilliance in a geometric shape
- Intensifies colour — ideal for fancy coloured diamonds
Ideal Settings
- Solitaire
- Three-stone
- Halo
- Bezel
- Channel
Advantages
- Combines step-cut silhouette with brilliant-cut sparkle
- Trimmed corners are more durable than sharp corners
- Excellent for coloured diamonds — intensifies hue
- Available in square and rectangular ratios
Considerations
- Can face up smaller than expected if cut deep
- Less well-known — fewer comparison benchmarks available
- Depth percentage varies widely between stones
Size Guide
A 1-carat square radiant measures approximately 5.5 x 5.5mm. For rectangular, look for 1.15-1.35:1 ratio. Radiants work beautifully as centre stones flanked by tapered baguettes.
History & Origins
Henry Grossbard, an Austrian-born master cutter working in New York, spent thirty years on the radiant cut. He started work in the late 1940s and did not patent the final design until 1977. His goal was to solve a problem that had frustrated diamond cutters for decades: how do you make a rectangular diamond sparkle? Before the radiant, rectangular diamonds meant step-cut facets (emerald, Asscher) — beautiful but subdued. Grossbard applied brilliant-cut faceting to a rectangular outline with trimmed corners, creating something that genuinely had not existed before. The radiant received one of the first patents ever issued for a diamond cut.
Buying Advice
The radiant's 70 facets do two things. They produce a dense, shimmering sparkle pattern that is more energetic than most shapes. And they are forgiving — all those facets break up inclusions, so you can often choose a lower clarity grade (SI1) without visible impact. That is a practical advantage worth knowing about. The trimmed corners give the radiant an octagonal outline that distinguishes it from the sharp-cornered princess, and they are also structurally stronger, which means less risk of chipping. For ratio, 1.00-1.05 for square, 1.15-1.35 for rectangular.
Browse Radiant Diamonds
Browse our live inventory of radiant diamonds — GIA and IGI certified.