How to Choose a Cushion Cut Diamond

August 5, 2025

Model wearing the Melanie Casey Windlass Ring with a Cushion Cut center stone.

Choosing a diamond for your engagement ring might feel like a daunting challenge, but we’re here to make it easy! When shopping for an engagement ring, it's common to wonder exactly which of the 4Cs (cut, color, clarity, and carat) is most important for that particular diamond cut, and in this case, the elongated cushion cut. As an expert stone sourcer, founder and designer Melanie Casey knows exactly what to look for when sourcing the best diamonds for elongated cushion cut engagement rings.

Ultimately, each of the 4Cs is important when it comes to choosing an elongated cushion cut diamond, and Melanie has recommendations that span from natural to lab grown diamond engagement rings.

Model wearing the Melanie Casey Snowdrift Bezel Set Ring with a Cushion Cut center stone.

Cut

Cut refers to how your diamond interacts with light: how much it sparkles, how well it scintillates, how much fire (colored light) is released from the diamond. While cut is the hardest of the 4Cs for non-diamond experts to quantify, Melanie’s recommendation makes selecting the right stone for an elongated cushion cut diamond ring the simplest step of all!

Melanie recommends setting your cut minimum to Very Good (or VG), which ensures that every elongated cushion cut diamond you see will be eye-clean, very sparkly, and perfectly symmetrical.

Model wearing the Melanie Casey Threaded Ring with a Cushion Cut center stone.

Color

A diamond’s color exists on a scale of completely colorless to light brown. The more colorless the diamond, the higher the color grade. While champagne diamonds have their own unique beauty, if you’re looking for a white elongated cushion cut diamond, Melanie has specific recommendations to ensure a bright white focal diamond.

Lab grown diamonds tend to be warmer than natural diamonds, so Melanie likes to go higher on the color scale when sourcing a lab grownelongated cushion cut diamond. Typically, she’ll set the color scale to F and above for lab grownelongated cushion cut engagement rings and G and above for a natural elongated cushion cut diamond ring.

Model wearing the Melanie Casey Whisper Ring with a Cushion Cut center stone.

Clarity

The diamond clarity grade reflects any flaws or inclusions within the diamond. Because an elongated cushion cut diamond is a brilliant cut, and therefore less transparent than a step-cut like an emerald cut diamond, inclusions will not show as clearly.

Just like color, designer Melanie Casey measures clarity differently for lab grown diamonds and natural diamonds. We’ve found that natural diamonds tend to be held to a higher standard, at least in the many, many diamonds we've evaluated over the years. For a lab grown diamond, Melanie recommends an elongated cushion cut with a VS1 clarity grade or higher. The clarity of a natural cushion cut diamond can start at VS2.

Model wearing the Melanie Casey Formation Ring in Cushion Cut.

Carat

The carat refers to the weight of the diamond, and unlike the other 4Cs, is completely subjective. At the end of the day, carat weight comes down to your personal style preferences and budget. Melanie’s recommendation when navigating our diamond selection tool is to set your preferences for color and clarity, then allow your budget to determine your carat weight.

Longing for Elongated?

While every cut, color, clarity, and carat recommendation from designer Melanie Casey applies equally to a square cushion cut diamond, if you want an elongated cushion cut engagement ring, you must also consider the length-to-width ratio of each cushion cut diamond.

As their name suggests, an elongated cushion cut engagement ring will have a longer length than width. As you peruse the diamonds available for selection, you’ll be able to tell if the diamond looks elongated based on the thumbnail photo next to the diamond’s stats. If you click on the diamond to find more information, you will see the measurements for that stone listed alongside the color, clarity, polish, and symmetry.

An elongated cushion cut will have a length-to-width ratio of at least 1.1. To find the length-to-width ratio of a cushion cut diamond, divide the length by the width. As the ratio increases to 1.2 or 1.3, the elongated cushion cut diamond will appear longer and therefore more dramatic.

Model wearing the Melanie Casey Hemisphere Ring with a Cushion Cut center stone.

We're Here to Help!

Even with Melanie’s expert advice, choosing the perfect diamond can feel overwhelming! Our experienced diamond experts are always ready to talk you through finding the perfect diamond for your elongated cushion cut engagement ring. They can offer suggestions specific to an elongated cushion cut engagement ring or even choose an elongated cushion cut for you based on your specific needs. If there’s an elongated cushion cut diamond ring in the collection that you loved that’s no longer available, our diamond experts can source a diamond for you that hits the same marks. No matter where you are in the process, you’ll speak to a real human who wants to help!

Cushion Cuts, Made to Order

Photo showcases a model wearing the Melanie Casey Touchpoints Ring with an elongated Cushion Cut center stone.

From the Top!

Always choose diamonds with a cut grade of Very Good (VG) or above
A bright white, lab grown, elongated cushion cut diamond: F+ color and VS1+ clarity
A bright white, natural, elongated cushion cut: G+ color and VS2+ clarity
Carat weight will depend on your preferences and budget
An elongated cushion cut diamond has a longer length than width, with a length-to-width ratio of at least 1.1

Our diamond experts can help you source the perfect diamond