The radiant cut

The radiant cut is among the most popular fancy cuts available. Unique, modern and chic, the radiant cut exudes class and is definitely a talking point! It is one of only two square cuts (along with the princess cut) that displays a high level of brilliance and sparkle.

In this article, we point out all the reasons why a radiant cut diamond might be the perfect choice for you.

What is the radiant cut?Radiant shape diamond

The radiant cut was created and patented in 1977 by Henry Grossbard, a master gem cutter. He wanted to create a cut that combined the fiery sparkle of a round brilliant with the elegant shape of an emerald.

If you have seen an emerald shaped diamond, you will notice that it is cut in long steps that can dull the brilliance of the stone and make it appear glassy. The round cut, on the other hand, has a specific and intense faceting pattern that brings out brilliance and sparkle. Cross the emerald and round cuts and you have the basis of the radiant cut.

The cut generally has about 70 facets.  Compare this to the famous round brilliant which only has 58 facets and you start to gain a sense of appreciation for the work that goes into this cut!

Because of its faceting pattern, radiant cuts have exceptional light return, making it highly brilliant. Hence the name radiant!

In fact, this brilliance is only outdone by that of the round cut.

The radiant cut - The clarity factor

The radiant cut is generally excellent at hiding inclusions that may be present in your diamond. Again, this is due to its many facets, which makes it difficult to see small impurities with the naked eye.

You can use this to your advantage when buying a diamond by dropping a few grades down on the clarity scale. The diamond clarity scale ranges from Flawless to Included. The less included the stone, the more expensive it becomes. If your diamond is less than 1 carat, you can drop down to VS2 while if it is over 2 carats, go down as far as VVS2 for excellent clarity.

Because inclusions will be more visible on larger stones, it’s best not to compromise on quality in this aspect. Before purchasing, ensure that you have seen the stone in person or viewed high quality photos and/or videos to be certain that it is eye clean (meaning no visible inclusions).GIA diamond clarity chart

The radiant cut - color

The color grade you choose can depend on the metal of the setting as well. For example, if you are opting for yellow or rose gold metals, you can drop down the color grade of your diamond to the near colorless grades or even the faint yellow grades, depending on your preferences and the appearance of the ring. The reason is that set against the metal, the tints in the stone will be less noticeable.

However, if your setting is white gold, platinum or silver then it is wise to choose from one of the colorless D-F grades as these metals tend to show any hint of color in the diamond.Diamond color chart from perfect colorless to noticeable color

You might have heard that when it comes to colored diamonds, fancy shapes are best. This is especially true of the radiant cut which is a very popular shape for colored diamonds. The shape, faceting and proportions of the cut maximizes and intensifies the color of the diamond. It exhibits the diamond color evenly throughout the stone, whereas some other shapes may have lighter areas due to the facet patterns.Radiant cut diamond color

Radiant cut – length-to-width ratio

You might have noticed by now that a radiant cut can be either square or rectangular. The cut will be the same, with only the length to width ratio slightly different.

For the perfect rectangular shape, choose a length to width ratio of about 1.25 – 1.35. For a square shape, choose a length to width ratio of 1.

If you are shopping online for an engagement ring, keep the length-to-width ratios in mind. While in the past rectangular radiant cuts were more popular, today, an increasing number of shoppers opt for the square shape. The shape you decide to choose depends on your personal preferences.

radiant shape diamond Length to widt ratio

The radiant cut - Durability

Some gemstone cuts, such as pear and marquise, can be quite fragile due to their pointed corners. These can chip and catch on things.

The radiant cut, however, is quite durable. The cut has trimmed corners and beveled edges which keep it from easily chipping or breaking. This is another reason the radiant cut is an excellent choice for an engagement ring as it can be worn daily without needing extra setting protection.

Why it’s important to see the radiant cut before you buy

Most diamond grading labs, including the GIA, do not grade the quality of the Cut of fancy shaped diamonds (a fancy shaped cut is all cuts other than the round brilliant cut). These labs only grade the Cut of the round brilliant.

What does this mean for you?

You will not have a clear idea of the quality of the fancy shaped diamond without actually seeing the stone. Poor cut quality can give rise to issues such as bow-ties which is detailed below.


This refers to the darkened area, in the shape of a man’s bow-tie, which may lie across the middle of the diamond. Bow-ties are mostly prevalent in elongated diamond shapes, such as pear, oval and marquise and can range from invisible to severe. The images below taken from James Allen all show some degree of bow-tie.

This occurs when misaligned facets on the diamond’s surface prevents light from reflecting off the stone. Instead of reflecting back at the observer, light travels through and out of the diamond. If the diamond has been expertly cut, with the facets perfectly aligned, then this will not be an issue.

Unfortunately, because the grading report does not grade Cut, the only way to be sure there is no unsightly bow-tie on the diamond is to actually see the stone for yourself. This is why buying blind (just going by a grading report and not seeing images of the actual stone) is not recommended.bow tie diamond radiant cut

Choose the setting for the radiant cut

Because the radiant cut is a durable shape, you have a lot of setting options that will work with it. The prong setting is generally the most popular choice for radiant cuts, allowing the stone to be viewed and admired in all its glory with minimum metal to block the diamond.

The best prong setting in terms of diamond visibility is the 4-prong option, while 6 and 8 provide more security but less visibility. If security is your highest priority, then a bezel setting may suit you best.

Because it is such a versatile shape, the radiant cut fits a number of ring styles. As a solitaire, the radiant cut is able to shine (literally and figuratively) as it shows off its special cut. You can opt to have a three stone setting, of a radiant set with trilliants, ovals or rectangular radiant stones as accents.

For detailed information about ring settings, see: Ring styles and settings  

Is the radiant cut expensive?

When most people hear the term ‘fancy cuts’ they assume that this means the diamond is more expensive.

Quite the opposite.

From all the diamond shapes, the round brilliant cut is the most expensive. Round diamonds use only about half of its rough, with the rest going to waste. So essentially you’re paying more for less. The radiant cut, on the other hand, retains most of its rough.

So how does this impact?

You have a bigger stone at a lower price compared to a round cut diamond.

Having said that, also note that the radiant cut is quite a deep cut, so it will not look as large as a diamond with a shallower cut, such as an emerald.

Shopping for the radiant cut

While most retailers offer diamonds with the radiant cut, it can sometimes be difficult to find what you are looking for due to the low availability of radiant cuts. A quick search on the James Allen website at the time of this writing brought up 88,605 round cut diamonds and only 2,748 radiant cuts!

When you have found your ideal diamond, don’t forget to request the certificate of authenticity and ensure that the diamond has been graded by a recognized lab (GIA, IGS and AGL are some). If buying a vintage or antique ring, you will not receive a diamond certificate as the diamond is already mounted in its setting. Instead, ask for an appraisal and certificate of the ring’s authenticity.

Finally, make sure that you have seen the diamond before you purchase, either in high quality images and videos or in person to avoid nasty surprises, and check the after-sales services, just in case of any issues.