What Is a Cushion Cut Diamond? The Complete Guide

The name is literal. A cushion cut looks like a small pillow or cushion: a square or slightly rectangular body with four sides that bow out very gently and four corners that are rounded off rather than left sharp. Older names for the same idea include "pillow cut" and "candlelight cut," the second a nod to how these stones were made to glow under lamplight before electric light was common.

The rounded corner is the single feature that makes a cushion a cushion. A princess cut has sharp, right-angle corners. A radiant has cropped, angled corners. A cushion softens those corners into curves, and that one change is what gives the shape its rounded, forgiving character. If you want the full map of how cushion sits next to every other outline, our diamond shapes guide lays them out side by side.

A cushion is a brilliant cut, which is the same faceting family as a round brilliant. Brilliant faceting uses large, triangular and kite-shaped facets that radiate out from the center, and they are arranged to bounce light back up at the eye as sparkle rather than to act like flat mirrors. That is what separates a cushion from a step cut like an emerald cut, where long parallel facets give a calm, glassy flash instead.

Because the facets are broad and the outline is soft, a cushion produces a warm, rounded sparkle. It is less of a sharp, white strobe than a round brilliant and more of a soft, glowing return of light, which is exactly why the shape reads romantic. On a grading report the faceting shows up in the shape line as "Cushion Brilliant" or "Cushion Modified Brilliant." That word "modified" matters more than it looks, and the next section explains why.

Two cushions can share the same outline and still sparkle in noticeably different ways. The difference comes from the pavilion facets, the ones under the stone that you cannot see directly but that control how light breaks up. This gives you the two looks people describe as crushed ice and chunky, and it is the most important choice to understand before you buy a cushion.

A crushed ice cushion, often a "Cushion Modified Brilliant" with an extra row of small pavilion facets, scatters light into many tiny pinpoints. It looks like a glass of crushed ice or shaved ice: busy, shimmering, and full of fine glitter. A chunky cushion, often a plainer "Cushion Brilliant" with fewer, larger facets, breaks light into bigger, more defined flashes, closer to a bold hall of mirrors. Neither is better. They are two different personalities.

The takeaway is practical: decide which look you want before you compare stones, because two cushions of the same carat, color, and clarity can still look quite different in the hand. If you can, view the actual stone or a video of it face up, since the facet style shows up instantly in motion.

Rounded corners are not just a look. They are also the most practical thing about the shape. A diamond is the hardest natural material there is, a 10 on the Mohs scale, but hardness is resistance to scratching, not to a sharp knock. The vulnerable spot on any diamond is a sharp point or a thin corner, because that is where a hard blow can chip it. A cushion has no sharp points at all. Its corners are rounded, so there is simply less exposed edge to catch.

That makes a cushion one of the more forgiving shapes for everyday wear and easier to set securely. The rounded corners tuck neatly under prongs or into a bezel without a prong needing to grip a fragile tip, which is the trade-off you accept with pointed shapes. If daily durability is high on your list, the cushion earns its reputation here. It is not a fragile stone, and the geometry is the reason.

Cushions come in a range from perfectly square to clearly rectangular, and the number that describes where a given stone sits is its length-to-width ratio. Take the length and width in millimeters from the report and divide the first by the second. A square cushion lands around 1.00 to 1.05, and anything up to roughly 1.10 still reads square to the eye. A rectangular cushion sits around 1.15 to 1.30, where the extra length becomes obvious. Push much past that and you are looking at an elongated cushion cut, which is its own distinct look.

The choice is about the effect you want. A square cushion looks full, balanced, and classic. A rectangular one lengthens the line of the finger and can look a little larger for its weight because the outline spreads. Cushions do hold some of their weight in depth, so they can face up a touch smaller than the flattest spreading shapes at the same carat, which is one more reason to judge a cushion by its millimeter measurements and its outline rather than by carat weight alone.

"Cushion cut" is really a small family, and knowing which member you want saves a lot of confusion. This guide is about the standard cushion: square to gently rectangular, modern brilliant faceting, the everyday classic. It has two close relatives that each deserve their own decision, and we have written each of them up in full so you can go straight to the one you want.

One point that ties the family together: the difference between these three is the shape and the faceting, not the material. All of them can be, and in our case are, Lab Grown Diamonds, which are real diamonds identical in material and hardness to mined ones. If the distinction between shape and cut quality is still fuzzy, our note on diamond cut vs diamond shape untangles the two terms.

The brilliant faceting works in your favor on clarity. All that sparkle, especially in a crushed ice cushion, breaks the surface into a busy pattern that camouflages small inclusions, so you rarely need to chase the very top clarity grades to reach an eye-clean stone. For most cushions, a VS1 or VS2 is a sensible, eye-clean target, and our comparison of VVS vs VS clarity shows why paying up to VVS often buys grading you cannot see. A chunky cushion is a little less forgiving, so if you choose that style, lean toward the higher end of VS.

Color is where cushions ask for a touch more attention. Because brilliant faceting concentrates light in the body of the stone, cushions can hold onto warmth a little more than some cuts, so a faint tint shows up more readily, particularly in larger stones and in warmer metals. This is a preference, not a defect: many people love a warm cushion set in yellow gold. If you want a cool, white look, aim slightly higher on color; if you like warmth, you can relax it and let the metal do some of the work. To read any of these grades off the paper with confidence, see our walkthrough on how to read a diamond grading report.

On budget, one honest note. Lab Grown Diamond prices have fallen substantially as growing capacity scaled up (Source: StoneAlgo, 2026), which means a cushion in a Lab Grown Diamond stretches further than it did a few years ago. Spend that room on the size and the look you actually want, not on a resale plan. A diamond is a love piece, not an investment, and it should not be bought as one: the ring is worn and kept, and its value is in what it marks, not in a price it might fetch later.

A cushion suits someone who wants a soft, warm, romantic look rather than the sharp white fire of a round brilliant. It carries a hint of vintage character while still being a modern, widely available cut, so it works for a buyer who likes antique-leaning style but wants a current stone. The rounded corners make it a strong pick for anyone hard on their hands or drawn to a shape that wears comfortably every day.

It also gives you room to tune the personality. Choose square or rectangular for the outline, and crushed ice or chunky for the sparkle, and you can land anywhere from a soft, glittering pillow to a bold, open, flashing stone. Few classic shapes offer that much range within one outline, which is a large part of why the cushion has stayed popular for as long as it has.

Stienhardt is a New York City jeweler that sources Lab Grown Diamonds and hand-sets and finishes them in NYC, selling direct to consumer. That means we own and inspect every stone we sell and hand you its independent grading report rather than drop-ship it, so you can confirm the shape, the faceting style, and the measurements on paper before you commit. Viewings are by appointment.

With a cushion, that inspection matters more than usual, because the crushed ice or chunky decision does not show up in the carat, color, and clarity numbers alone. It lives in the faceting, and it is best judged with the stone in front of you or on video. Tell us which look you want, square or rectangular, glittering or bold, and we will match you to a stone whose report and outline actually deliver it. A name on a listing is marketing. The report and the stone are fact.

If you would rather judge a stone in person, we show by appointment in New York. Book a viewing.