The Diamond Pro

Radiant Cut Diamond Guide: Quality, Clarity, Color and Cost

By Michael Fried

Scared of getting ripped off? Don’t want to waste your money? Confused by all the choices? Contact us.

Bottom Line Recommendation

A Radiant Cut Diamond offers outstanding brilliance and durability. For Color, we recommend an H or better, like this stunning H graded Radiant Cut in a 14K white gold setting. For Clarity, we suggest an SI1 or an SI2. When it comes to Cut quality, we recommend seeking the assistance of an expert to ensure you end up with an extraordinary diamond at an excellent price.

The Radiant Cut Diamond

Popular since the 1980s, the Radiant Cut Diamond lives up to its name: it is impressively radiant and brilliant. Henry Grossbard designed the Radiant Cut in 1977 in pursuit of combining the finest elements of the Round Brilliant Cut and the Emerald Cut.

The Radiant Cut Diamond owes its brilliance to the 70 facets found its pavilion and crown. The precision of each facet offers immense brilliance and fire. The Radiant Cut’s brilliance is surpassed only by the Round Brilliant Cut.

With carefully beveled corners, Radiants have substantial durability against chips and breakage—making it an excellent choice for those with an active lifestyle. This feature also allows the Radiant to be paired alongside both square and rounded diamonds, like in this 1.0 Carat Radiant in a 14K white gold channel setting.

Radiant vs. Cushion Cut Diamonds

While Radiant and Cushion Cut Diamonds contain similarities, they have distinct differences when it comes to Cut and appearance. Both showcase trimmed corners for increased stability, though Cushion Cuts have more rounded edges while Radiants carry distinct edges.

The numerous facets and large table of the Radiant provide exceptional, hard-to-beat brilliance. The Cushion Cut also offers brilliance, but is better known for its immense fire (colored light reflections).

Though length to width ratios are dependent on personal preference, Radiant and Cushion Cuts are available in an array of square to rectangular compositions. More often than not, Cushion Cuts are purchased with a length to width ratio of 1.0-1.09, which is indicative of a more squared shape than Radiants.

Cushion and Radiant Cuts are distinct shapes and choosing one over another is purely based on personal preference. To make the best decision, consider the loved one receiving the stone and their personal style. If you’re still unsure which to choose, contact our experts for more advice and direction.

You can also peruse recently purchased rings from our highest rated retailers to see what you like.

Radiant Cut Diamond – Quality

Radiant Diamonds are created with a modified brilliant cut facet pattern for both the pavilion and crown, giving this diamond its high level of brilliance (the amount of white light reflected back to the eye or ‘sparkle’). Because Cut is vital to any Diamond’s beauty, especially the Radiant Diamond, a careful eye must be used when considering stones for purchase.

The GIA only grades Cut quality for Round Brilliant Diamonds. A GIA certificate for a Radiant Cut will not include a Cut grade and is therefore not indicative of how the diamond truly looks. Radiant Diamonds must be evaluated by your eyes and, ideally, the eyes of a professional.

As a rough guideline, we offer suggestions for evaluating a Radiant Diamond’s Cut.

Radiant Cut Diamond – General Cut Guidelines

ExcellentVery GoodGoodFairPoor
Table %61-6957-60 or 70-7254-56 or 73-7451-53 or 75-79<51 or >79
Depth %61-6759-58.9 or 70.1-7454-56.9 or 74.1-7954-56.9 or 74.1-79<54 or >79
GirdleVery Thin – Slightly ThickVery Thin – ThickVery Thin – Very ThickExtremely Thin – Extremely Thick
CutletNoneVery SmallSmallMedium>Medium

Be sure to also look at the corners of a Radiant, ensuring they are even and not too wide—or too narrow. The cropped corners of the Radiant give it stability, but also need to be symmetrical in order to maintain the overall beauty.

For one-on-one guidance on choosing a high quality Radiant Cut Diamond, contact our experts today.

Radiant Cut Diamond – Length to Width Ratio

A diamond’s length to width ratio signifies how proportionate the diamond is with its intended shape (i.e. square vs. rectangular) and is determined by dividing the diamond’s length by width. As an example, if a diamond’s length measures 5mm and its width is 3.5mm, the length to width ratio is 1.43.

The ratio you choose for your Radiant Diamond is entirely dependent on what you find to be the most aesthetically pleasing. A common range for Radiant length to width ratios is 1.00-1.35, with the lower end indicating a more square shape. Length to width ratios can go up to 2.0 for a more rectangular shape.

ExcellentVery GoodGoodFairPoor
Square1.00–1.031.04-1.051.06-1.08 or >1.08>1.08
Rectangle1.20-1.301.15-1.19 or 1.31-1.351.10-1.14 or 1.36-1.401.08-1.09 or 1.41-1.50<1.08 or >1.50

You’ll notice the diamonds in this illustration vary in their ratios. From the lower end, 1.15, the Diamond is close to a square shape, while the higher end of 1.35 boasts a more vivid rectangular shape. Review several different length to width ratios before deciding on what you prefer.

Radiant Cut Diamond – Clarity

Clarity describes how clean a diamond is. In other words, it measures of how free of inclusions and blemishes it is.

The GIA ranks Clarity on the following scale:

  • IF – Internally Flawless
  • VVS1 – Very Very Small Inclusions
  • VVS2 – Very Very Small Inclusions
  • VS1 – Very Small Inclusions
  • VS2 – Very Small Inclusions
  • SI1 – Small Inclusions
  • SI2 – Small Inclusions
  • I1 – Inclusions
  • I2 – Inclusions

The difference in appearance between two adjacent grades, such as VVS1 and VVS2, is rarely distinguishable to the naked eye.

In addition, Radiants are cut with many facets and angles, making them look like crushed ice. This Radiant Cut in a 14K white gold solitaire setting demonstrates the unique cracked ice appearance. Because of this feature, inclusions and flaws are more easily hidden. For this reason, we generally recommend Radiant Cut Diamonds in a Clarity of either S1 or S2, to ensure you’re not paying for a feature that won’t be noticed.

More than anything, we recommend carefully reviewing a Radiant Cut Diamond for inclusions and blemishes, and having an expert assist you.

Radiant Cut Diamond – Color

In addition to Cut and Clarity, you’ll want to review Radiant Cuts for their Color. As graded by the GIA, Color rankings range from D to Z. The D grade represents the most clear, colorless diamonds while the Z grade represents those with noticeable yellow or brown tint.

The differences in Color for Radiant Cuts are slightly easier to perceive than other diamond shapes. Still, we generally recommend an H Color or better for Radiant Cut Diamonds, allowing your budget to be spent on other aspects, like Cut quality. To the naked eye, an H grade will appear white and colorless to the naked eye.

You’ll also want to make sure your diamond appears white in relation to its setting. For example, even this J Color Radiant Cut Diamond looks colorless in a 14K yellow gold solitaire setting. Depending on the setting you choose, you have flexibility with your Color range—ensuring you spend in the most important area: Cut quality.

Radiant Cut Diamond – Certification

While many lab grading entities issue reports for Radiant Cut Diamonds, only a couple entities are trustworthy. Based on our many years of experience, we’ve found the GIA and AGS grade diamonds consistently and accurately, while other labs are dangerously inconsistent.

We strongly suggest only considering Radiants that have certificates issued by either GIA or AGS. Diamond sellers that consistently offer these certificates include James Allen and Blue Nile.

In addition to receiving a lab report, you’ll want to review any diamond thoroughly before making a decision. Lab reports do not indicate how the diamond will appear. True beauty and appearance can only be assessed by you and an expert.

Shop for radiant cut diamond enegagement rings here.

Because Radiant Cuts have such potential for brilliance, we suggest having an experienced diamond professional assist you to ensure maximum sparkle at an excellent price.


For a diamond that bursts with brilliance and sparkles from across the room, consider a Radiant Cut Diamond. Ensure you closely review each Diamond for its Cut quality, Clarity and Color—along with overall beauty and appeal.

Contact our experts to ensure your Radiant Cut Diamond lives up to its name—and price.

About the author
Mike learned the diamond business from the ground-up at Leo Schachter Diamonds - one of the world's top diamond manufacturers. He has been recognized as a diamond industry expert by Time, PeopleMoney, The Daily Mirror, NerdWallet, The Times Herald, Yahoo Finance Australia, The Art of Charm, The Washington Diplomat, The Next Web, and more. See more
Top Recommended Vendors
James Allen James Allen is the leader in online diamond sales. Their imaging technology is at the point where it's almost the same as inspecting a diamond with a jeweler's loupe. Their customer experience is best in class, and they have recently upgraded their non-engagement jewelry inventory as well.
What we love about them:
  • No questions asked returns within 30 days of shipment. James Allen will send you a paid shipping label to return the ring.
  • Lifetime Warranty
  • Free International Shipping
  • Free prong tightening, repolishing, rhodium plating and cleaning every 6 months
  • Provide insurance appraisals
  • One free resizing within 60 days of purchase
  • Free ring inscriptions
  • Best-in-class high quality imagery of all diamonds in stock
  • 24/7 Customer Service
  • Best-in-class packaging

Blue Nile Blue Nile is the largest and most well known internet jewelry seller. They have the industry-leading largest available exclusive online inventory. Their high quality images are catching up to James Allens' and their prices are amazing. 
What we love about them:
  • No questions asked returns within 30 days of shipment. Blue Nile will send you a paid shipping label to return the ring.
  • Lifetime Warranty
  • Free Shipping
  • Free prong tightening, repolishing, rhodium plating and cleaning every 6 months
  • Provide insurance appraisal
  • One free resizing within the first year of purchase
  • High quality images of about half of their diamonds
  • 24/7 Customer Service
  • 100% credit towards future upgrades (must be at least double in value)
  • Best in class fulfillment

Still afraid of getting ripped off?

Before you buy a diamond, get personal buying advice from industry veterans. We'll help you get the best diamond for the money.

Ask your diamond purchase question here

  • This field is for validation purposes and should be left unchanged.

DISCLAIMER: We don't use your email for marketing. Period.

Why we are doing this for free?

Click for Diamond Purchase Advice 100% Free

Ask your diamond purchase question here

We are a team of diamond experts who will teach you to identify scams and avoid spending money on features you can't see. Tell us as much information as possible to help us help you (ie, budget, preferences, etc)

  • This field is for validation purposes and should be left unchanged.


DISCLAIMER: We don't use your email for marketing. Period.

Please enter your email address to receive your personal code:

Here is your coupon code: GFDSF3GF