Radiant vs Cushion Cut Diamonds: Which Should You Choose?

Radiant vs cushion cut: what is the difference?

Both shapes start from the same idea: a square or rectangle with the sharp corners taken off. The difference is how the corners are softened and how the sides are shaped. A radiant keeps straight, parallel sides and has its corners cropped (cut off in a short straight line), so it looks like a rectangle or square with clipped corners, almost octagonal. A cushion has gently curved sides and rounded corners, like a pillow seen from above. That one change in outline shifts the whole character of the stone.

Both are brilliant cuts, meaning they use many triangular and kite-shaped facets to break light into sparkle, rather than the long parallel steps of an emerald cut. If you want to see where each sits among the other shapes, start with our overview of every diamond shape, or go straight to the family comparison of princess, radiant, cushion and Flanders cuts compared. Any unfamiliar word here is also defined in our plain-English jewellery glossary.

What is a radiant cut diamond?

The radiant was introduced in the late 1970s by cutter Henry Grossbard, who wanted the outline of an emerald cut with the sparkle of a round brilliant. He combined the two: the rectangular, corner-cropped outline of a step cut on top, and brilliant-style faceting on both the crown (the top half) and the pavilion (the bottom half). The result usually has around 70 facets, more than the 57–58 of a round brilliant.

Because the corners are trimmed rather than pointed, a radiant is far less likely to chip than a princess cut, which has four sharp corners. Our guide to how a radiant differs from a princess sets that out in detail. Against the emerald cut, a radiant hides inclusions (small internal features) much better, because its busy facet pattern breaks up the view into the stone; the emerald vs radiant comparison shows why.

Radiants come in two main forms. A square radiant, with a ratio of about 1.00–1.05, sits close to a cushion in outline; see our page on square radiant diamonds. A rectangular radiant, at about 1.20–1.35 or longer, is the more common choice for engagement rings today. Everything else about the cut, from depth to colour advice, is in our complete radiant cut guide.

What is a cushion cut diamond?

The cushion is one of the oldest diamond shapes still cut. It grew out of the old mine cut, a hand-cut, softly squared diamond from the 1700s and 1800s with a small table, a high crown and large facets. The modern cushion keeps that soft outline but adds more precise faceting; our page on the old mine cut that cushions grew from traces the family line.

Today there are two broad styles, and grading reports often use both names:

• Cushion brilliant: usually about 58 facets with larger, chunkier facets. It gives bold, separate flashes of light, sometimes called an antique or 'chunky' look.
• Cushion modified brilliant: extra facets on the pavilion, often 64 or more, which break light into many tiny sparkles, known as a crushed-ice look.
• Hybrids: some cutters mix the two, aiming for chunky facets with a little extra scintillation (the flicker of light as the stone moves).

Cushions also come square (about 1.00–1.05) or elongated. For buying detail across all of these, our cushion cut buying guide goes further. If you are also weighing a step-cut square, the Asscher vs cushion guide is the closest comparison; if a round is still on your list, read the round vs cushion comparison.

Radiant vs cushion cut: which sparkles more?

Both are bright, but the sparkle feels different. Diamond has a refractive index of about 2.42, meaning it bends light strongly; how the facets are arranged decides whether that light returns as big flashes or fine glitter.

• Radiant: its 70 or so facets and straight edges usually give a lively, even, crisp sparkle across the whole face, often with a fine crushed-ice texture. It tends to look bright under shop lights and office lighting alike.
• Cushion brilliant: fewer, larger facets produce broader flashes of white light and of colour (the coloured flashes are called fire). It can look calmer in dim light and more dramatic under a single spotlight.
• Cushion modified brilliant: a crushed-ice pattern that can look very similar to a radiant, but within a rounder outline.

Neither shape gets an overall GIA cut grade the way a round does, so you judge sparkle by eye, from video and from the proportions on the report. Both can show a bow-tie, a dark band across the middle where light leaks out, most often in elongated stones. A faint bow-tie that comes and goes as the stone turns is normal. One that stays dark at every angle is a sign of weak proportions.

Crushed-ice cuts have one quirk worth knowing: they can hide inclusions well, but they can also look slightly 'busy' or glassy in the centre if the stone is too deep. Chunky cushions show the inside of the stone more clearly, so clarity matters a little more.

Which looks bigger, a radiant or a cushion?

For the same carat weight, a well-cut radiant and a well-cut cushion usually face up (the size you see from above) within a few tenths of a millimetre of each other. What changes the visible size most is depth, not shape. A stone cut deep carries weight below the girdle (the outer edge) that you pay for but cannot see.

Cushions are the shape most likely to carry hidden weight. Many are cut with a deep pavilion or a bulging outline, and depths above about 70% are not unusual; our page on how depth hides weight in cushions explains how to spot it. Radiants can be deep too, but more of them sit in the 61–67% range.

Elongated shapes look larger for their weight and slim the finger. A rectangular radiant at 1.20–1.35 reads clearly as a rectangle, while an elongated cushion at 1.10–1.25 stays softer and closer to an oval. For the ratio maths, see the radiant ratio guide, plus our pages on elongated radiants and elongated cushion shapes.

Do cushions show more colour than radiants?

Both shapes hold body colour (the faint yellow or brown tint in white diamonds) more than a round does, because their corners are thicker and light travels further inside the stone. Cushions are a little more prone to it, especially chunky cushions and deep ones, where warmth gathers in the corners. Our page on why cushions can show more body colour goes through the optics.

• Radiant in white gold or platinum: G–H colour usually looks white face-up.
• Cushion in white gold or platinum: many people prefer F–G, or H if the stone is not deep.
• Either in yellow or rose gold: I–J can look white against the warm metal.
• Clarity: VS2 or a well-chosen SI1 is usually eye-clean (no inclusions visible without magnification) in a radiant or crushed-ice cushion; a chunky cushion may need VS2 or better.

That colour-holding habit is also why both shapes are popular for fancy coloured diamonds. Radiants in particular are a favourite for yellow, pink and blue stones, because the facet pattern intensifies the colour face-up.

Radiant vs cushion cut engagement ring: which is more durable and how is each set?

Diamond is 10 on the Mohs hardness scale, but hardness is not toughness: a thin edge can still chip if it takes a hard knock. Neither shape has sharp points, which is a big part of their appeal for everyday wear. A radiant's cropped corners are short straight edges; a cushion's rounded corners are thicker again. In practice both are about equally sturdy, as long as the girdle is not cut extremely thin.

• Four claws: the usual choice. On a radiant, claws sit on the cropped corners; on a cushion, round or double claws hug the curves.
• Double claws: eight claws in pairs add security and suit a vintage-style cushion.
• Halo: very common with cushions, where a halo of small diamonds makes the centre look larger; with radiants a halo can follow the cropped corners for a tailored look.
• Hidden halo: a ring of small diamonds under the centre stone, seen from the side only.
• Bezel: a rim of metal around the edge, very secure and modern, suits a radiant's straight lines.
• Side stones: tapered baguettes or trapezoids suit radiants; pear or round side stones suit cushions.

For design ideas, see our radiant cut engagement ring styles. Whichever shape you choose, the claws should sit at the corners so the thinnest part of the girdle is covered.

Radiant vs cushion cut price: natural or lab-grown?

Radiants and cushions are cut from both natural and laboratory-grown diamond. Lab-grown diamonds are real diamond, with the same hardness and refractive index, grown in a laboratory rather than mined; they cost much less than natural and are easy to find in larger sizes. Both kinds should come with an independent grading report, for example from GIA or IGI, which states whether the stone is natural or lab-grown.

These are broad ranges only and move with the market and the exact grades. Both shapes usually cost less per carat than a round of the same weight, colour and clarity, partly because cutters keep more of the rough crystal. Between the two, prices are close; deep cushions can look cheap per carat but deliver less visible size, so compare price against millimetres, not just weight.

How do you choose between a radiant and a cushion? Step by step

1. Decide on the outline. Straight sides and clipped corners (radiant) or curved sides and rounded corners (cushion)?
2. Pick square or elongated. Square is 1.00–1.05 for either; elongated is about 1.20–1.35 for a radiant, 1.10–1.25 for a cushion.
3. Read the report. Confirm shape, measurements, depth, colour, clarity, polish, symmetry and whether the diamond is natural or lab-grown.
4. Check depth. Aim for roughly 61–67% on a radiant and under about 68–70% on a cushion, so you are not paying for hidden weight.
5. Watch a 360° video. Look for a fixed dark bow-tie, a glassy centre or inclusions near the corners.
6. Match colour to metal. Allow a grade higher for a cushion in white metal; I–J often works in yellow or rose gold.
7. Plan the setting. Choose claws, a halo or a bezel that cover the corners before you commit to the stone.