This page contains references to diamonds or engagement rings from different companies. Sometimes I do receive a commission when you click on links and buy the products.

Unique and deserving of its name, the radiant cut takes elements from both round and emerald cut diamonds to create a stone with fire, depth and, of course, intense radiance.

Henry Grossbard designed the cut in 1977 and it has held popularity since the early eighties. The pattern is one of 70 facets in the pavilion and crown of the diamond, with each contributing to the striking fire and brilliance that can be seen in a radiant cut stone.

The corners of a radiant cut are beveled, making these diamonds as durable as they are beautiful. The cropped corners prevent the risk of chipping so a radiant cut may be suitable for someone with an active lifestyle.

While their bevelled finish is similar to that of a cushion cut, a radiant cut features a more defined silhouette when compared with the soft, roundedness of a cushion cut.

You may hear radiant cuts referred to as ‘Cut Corner Square’ diamonds or ‘Rectangular Brilliants’. For many, a radiant cut is the perfect balance between the clean, definite lines of a step-cut, but with the fire, brilliance and ‘sparkle’ of a brilliant cut. It is perfectly complemented by both round and square diamonds making it a flexible and stunning choice for jewelry.

James Allen has a good selection of radiant cut to choose from, but should you decide to revert to the classic styles such as a round or princess cut, then be sure to head to Whiteflash’s A CUT ABOVE® – they provide the best quality cut diamonds available.

Cut Quality

The GIA do not offer a cut grade for radiant cut diamonds. For this reason, it is essential that you familiarize yourself with the ratios and view the diamond yourself rather than relying on certification.

Needless to say, certification is still essential, as it will confirm the overall quality of the stone (color, clarity etc).

Although there are no officially agreed cut parameters for a radiant cut diamond, the below figures can be used as a general guide.

Length to Width Ratios

A large part of choosing the perfect radiant cut diamond will come down to the length to width ratio of the stone. Dividing the diamonds length by its width will give you the ratio, and this in turn will indicate the diamonds proportion in relation to its shape.

Selecting the perfect ratio will be dependant on your personal preference. Those who are seeking the elegant, elongated shape of an emerald cut but with the sparkle of a round brilliant may opt for a rectangular shape, while others prefer the aesthetic of a square.

It is worth noting that when a radiant cut diamond is set in a ring (particularly a standard prong setting) the bevelled corners are often hidden. This means that should you choose a square radiant cut, they will look very similar to a princess cut diamond.

The most common range for ratios is 1.0 to 1.35, however, it is possible to go beyond this (up to 2.0) if you are seeking a rectangular shape.

The ‘Crushed Ice’ Look

While exploring radiant cut diamonds, you may hear the term ‘crushed ice’. This term is used to describe diamonds which have multiple facets, causing reflections that give a look similar to crushed ice.

If we take a look at these diamonds from James Allen, you can see the diamond on the left seems to display more of the ‘crushed ice’ look, while the diamond on the right appears to have clearer more deliberate facets.

This phenomenon is extremely difficult to see in a photograph, therefore, it is best to view the diamonds in person or by using the 360-imaging offered by online vendors.

When considering cushion cuts, the crushed ice look is sometimes seen as a flaw. The seemingly random faceting tends to jar with the clear, chunkier facets of a cushion cut. However, that is not the case with radiant cuts.

Again, it is a matter of preference, with many enjoying the twinkling crushed ice look, particularly as it masks inclusions within the diamond.


The faceting of a radiant cut diamond makes it fairly forgiving when it comes to blemishes and inclusions. It will be possible to find a stunning SI1 or SI2 that is eye-clean (no inclusions visible to the naked eye).

As always, you must assess the diamond to ensure there are no imperfections at the very center of the stone or close to the surface of the table. An SI1 is the best clarity grade for a radiant cut, as it is the perfect balance between beauty and budget.


The yellow hues that come through in lower color grades are easier to detect in a radiant cut than in other cuts of diamond (such as round brilliant). For this reason, an H is the minimum color you should aim for when setting your diamond in a white metal. At this grade, the diamond will still appear colorless to the eye.

If you are choosing a warmer setting (i.e., yellow or rose gold, or warm colored side stones) a color grading of J would be suitable.

While color and clarity are important, it is not worth stretching your budget for features that will not be seen (for example, a D in color or an FL in clarity). The focus of cut quality as this will have the greatest impact on the aesthetic of your stone.

The Final Word

A radiant cut diamond can exude a brilliance and fire like no other. This striking cut is perfect for someone looking for a stunning sparkle that just a little different from the rest.

For the best diamond possible take a look at the impressive selections on James Allen and Blue Nile, who both hold a wealth of radiant stones, displayed with the best 360° imaging for the most in-depth view possible.

Richard Jenkins, The Diamond Guru

Get free assistance from the Diamond Guru today. You’ll be glad you did!

  • Secure the best quality diamond for your budget.
  • Don’t pay over the odds for your diamond ring.
  • Have piece of mind that you didn’t get ripped off.

Have a Question? Contact us now…

    Leave a Reply

    Your email address will not be published. Required fields are marked *