Radiant Cut Diamonds: The 2 Best Places to Buy (in 2023)

Last Updated on May 22, 2023 by Juli "Jewels" Church

Looking for the perfect place to buy radiant diamonds online?

You're in the right place! 

In this Learning Jewelry guide I'll answer common questions like:

  • What should you look for when buying radiant diamonds online?
  • Are radiant diamonds good for an engagement ring?
  • How do you know you’re getting a good deal?
  • What are the red flags to watch out for when buying?

The Best Places to Buy Radiant Diamonds Online

If you need the list quick, here are my top picks for finding radiant shaped diamonds from reputable online dealers. Keep reading for more information about each of these shops. 

  1. James Allen
  2. Blue Nile

1. James Allen

James Allen frequently holds a number one spot in our guide and it's easy to see why when you factor in all the benefits they give their customers. 

They've got a huge selection of loose diamonds. I'm talking hundreds of thousands. But for radiant cut diamonds, they carry around 1400 (minimum 1 carat, H color, VS2 clarity) natural diamonds. They also have around 500 radiant shaped fancy color diamonds. 

The selection of radiant diamonds at James Allen is a mixture between rectangular and square shape radiants.


They don't have a way to separate the two to make it easier. You just have to eyeball it as you scroll.

Fortunately you don't have to click in to each diamond and can quickly identify and eliminate unappealing diamonds. They even have a feature that lets you compare two side by side. The 360˚ video is controllable, smooth, and easy to see inclusions

When you buy a radiant diamond from James Allen, make sure that you are only buying GIA certified diamonds, not IGI. But we'll talk more about diamond certifications and grading reports in the FAQ. 

Their radiant diamonds aren't separated into any cut categories, so you'll have to pay attention to the proportions of the diamond to nail the best cut ones. You can check this without having to click to each individual diamond and use the ellipsis to bring up the length to width ratio, depth, and other diamond details. 

James Allen recently rolled out an additional feature to their ring settings. Currently, they carry just under 100 different settings, which is about 50 less than what they have for a lot of shapes. The new Ring Studio allows you to further modify ring settings.

You can choose two tone colors, such as a rose gold prong basket with a yellow gold setting. You can even add a surprise diamond or blue sapphire.  Just look for the rainbow ring emblem on the corner of the ring setting option and you can edit further. 

Lastly, one of the biggest advantages James Allen has over most of the other jewelry guys both in-store and online is their free lifetime warranty. This warranty will cover all that routine maintenance your jewelry will need over the years, such as prong retipping of rhodium plating white gold.  


  • Smooth, controllable viewing
  • Tailor setting using Ring Studio
  • Lifetime upgrade
  • Lifetime warranty


  • Small amount of radiants compared to other shapes

2. Blue Nile

blue nile cover 1

Blue Nile is always in close proximity to James Allen in our guides, as these two often battle for the number one spot. They've got a long-standing reputation as the first loose diamond dealer online since 1997, so they've built quite the customer base. 

They have one of the largest loose diamond inventories and carry around 1500 radiants with our standard cut grades and up to 3000 of them as whole.

Unfortunately, they don't have 360˚ viewing on all of them, which drops us down to about 1000. 

The viewer is nice, but some of the diamonds look a little far away for my liking. I prefer James Allen's viewer. 

Blue Nile's radiant diamonds are separated into a couple different cut categories, even if radiant cut diamonds don't have official cut grades. They separate them in Good, Very Good, and Astor Ideal. 

The Astor Collection is unique to Blue Nile and features the best cut diamonds they have to offer. The Astor Collection is made up of round diamonds, princess cut diamonds, cushion cut diamonds, and the square radiant cut.

In addition to the GIA grading reports that all of their diamonds come with, the Astor diamonds come with a GemEx report, which measures the light performance of the cut diamond. 

GemEx Light Performance Report

The GemEx report breaks down the exact percentage of white light, colored light, and light points being returned to the observer. More specifically, the brilliance, fire, and sparkle of the diamond.

A Gem Ex report isn't a necessity of a diamond. It doesn't raise the resale value of the diamond. It doesn't replace a grading report or diamond certification. 

Blue Nile's diamonds are priced a little higher than some online retailers like James Allen, but they make an excellent choice to buy a radiant diamond engagement ring from. They have many 250 ring settings to choose from. Keep in mind they separate settings by color metal as well, so many of them are duplicates.


The biggest thing about Blue Nile that grinds my gears is there lack of a warranty. Don't be fooled by the words "lifetime manufacturing warranty" because that doesn't cover the routine work all engagement rings need down the line. You'll pay for that out of pocket.


  • Lifetime warranty
  • Free sizing for a year
  • Lifetime upgrade
  • Clear 360 view
  • Cons

    • Not many choices in diamond fine jewelry 
    • Does not cover loss of stones in settings

    Radiant Diamonds FAQs

    Here's a list of some of the most popular questions asked about radiant shape diamonds: 

    Is It Cheaper To Buy Radiant Cut Diamonds Online?

    Not only is it cheaper to find a radiant cut diamond online than at a mega jewelry store like Kay or Zales, but you'll also have way more choices. 

    The business model of a brick and mortar store requires certain stipulations to order in diamonds for you to choose from, so you won't have too many choices outside of popular diamond shapes, like the round brilliant cut.

    Most rectangular shapes will be emerald cuts, not radiants. 

    However, in 2020, Kay, Zales, and Jared have rolled out loose diamonds on their online websites. Still the selection is much smaller and some are overpriced. 

    In addition to better prices and more choices, one of the biggest features of shopping for radiant diamonds online is that you don't have a salesperson breathing down your neck trying to convince you to buy something you're not quite sure you want. Online associates don't get paid commission for sales, so their advice is unbiased as well. 

    The business model of an online diamond retailer is cheaper because of the way diamond wholesalers and vendors conduct their business. It makes it less expensive for online retailers. On average, buying diamonds online could save your around 30% to 40%.

    Are Radiant Cut Diamonds More Expensive?

    On average, all fancy diamond shapes are going to be less expensive than a round brilliant diamond of the same grades. But compared to a marquise or an emerald cut diamond, they'll be more expensive.

    Marquise aren't large in table size and emerald cut diamonds are step cut. Step cut diamonds tend to be less expensive than brilliant cut shapes like the radiant diamond. 

    Here's where the price of a 1 carat radiant cut stone fits in with other shapes:

    radiant price

    What Should You Look For When Buying Radiant Cut Diamonds?


    Radiant cut diamonds have no official cut grade, though some retailers might separate their own inventory into different cut grade categories. This is done at the retailers own discretion because round diamonds are the only officially graded cut grades by the GIA.

    The American Gem Society gives princess and cushion cut diamonds ideal cut grades, but these are not exact symmetry. 

    With fancy shapes, you really have to eyeball and check out the nitty gritty diamond details. This includes length to width ratio, table size, polish, and symmetry. Radiant shapes have 70 facets and are considered to have the closest light performance to the round brilliant. 

    You really want to pay attention to the shape of the radiant. Whether you're looking at a square radiant or a rectangular radiant cut diamond, you'll want to make sure those cropped corners are even. One narrow corner could throw off the entire aesthetic. 

    In order to purchase the best cut quality of a radiant diamond, you'll want to choose one between a 1.20-1.30 for rectangular radiants and 1.00 and 1.03 for square radiants. Any L/W between these guidelines will give you the best brilliance for a radiant cut engagement ring.

    Consider what you want your engagement ring setting to be when deciding whether to go for a longer radiant or a shorter one. 

    Symmetry is also extremely important with radiants. 

    Most of them are slightly misshapen. Make sure that your polish and symmetry are Excellent. 

    Clarity and Color

    Brilliant cut diamond shapes like the radiant diamond are better hiding more subtle and even some obvious blemishes or inclusions. Step-cut diamonds like the emerald cut or the Asscher cuts reveal obvious inclusions, which is one of the reasons why they're cheaper than brilliant shapes. 

    So when choosing color grades for your radiant, it's not necessary to buy a VVS1 or VVS2 diamond. I usually recommend a VS2 because you'll have more eye clean options, but an SI clarity diamond will save you more money without too much of a difference. Just make sure you either go to see it with your naked eye or can see it through a crystal clear viewer to point out any dark inclusions. 

    Diamond color shows more tint in radiant shapes than others. Radiants normally appear larger than other shapes of the same carat weight and they allow jewelers and gemstone cutters to retain more of the diamond rough. The more diamond rough there is, the more color reveals itself. 

    For this reason, radiant cut diamond shapes are very popular for fancy colored diamonds. Many celebrities like Kelly Clarkson, Jennifer Lopez, and Hilary Duff all own colored radiant cut diamond rings. 

    The extra facets in a brilliant cut stone help some, but not as much as we'd like. For a radiant diamond, I'd recommend choosing between the G-H area, unless you prefer warmer diamonds. Some of our readers prefer tinted diamonds that complement their skin tone. 

    What are the Red Flags When Buying Radiant Diamonds Online?

    There aren't a lot of red flags with diamond shapes, but there are some things to be aware of. 

    Bowtie and Excessive Depth Percentage

    You might've heard of the bow-tie effect, a shadow that plays across the table area of certain diamond shapes. Usually this affects lower quality marquise, pears, and oval shapes, but can affect radiant cuts as well. 

    For those of you who prefer longer rectangular radiant cuts, just make sure it's not too long. That's when the bowtie will start to appear. Some people like the uniqueness of a bow tie, but most people see it as a shadow that holds back the brilliance of the diamond.

    A good 360˚ viewer will reveal any obvious bowtie online before you buy it. I'd recommend a controllable one so you can manually check angles. 

    The other thing you want to watch out for when picking out the best radiant diamond is the depth percentage. The depth percentage is part of the diamond details like polish and symmetry. Stick to a depth between 61-65%. Radiants that are too deep will diminish light performance

    Grading Report

    You've heard the words GIA, AGS, grading report and diamond certification thrown around throughout the article, so let's get down to the heart of why it's important. Most diamonds found in mega retailers are either uncertified or are certified by a cheaper and less reliable lab. 

    GIA and AGS graded diamond tend to have an extra premium in stores than they do when you buy from an online retailer. This is because it's more expensive for a place like Kay to get their diamond certified from the GIA.

    Online vendors already have the certification, so it doesn't cost the online retailer any extra money and they give it to you for cheaper.

    Those places use cheaper certifying labs like GSI or IGI. While some of our retailers do sell IGI diamonds, we recommend only sticking to GIA or AGS. When diamonds are appraised for their value or assessed for resale value, other certifications don't seem to matter. 

    The reason is because those other labs don't have as strict of guidelines when grading diamonds. It's possible to take a GSI certified diamond, have it graded at the GIA and find out they graded it as lower color and clarity grades. Diamond certifications from reliable labs protect you and make sure you're getting the diamond quality you're paying for. 

    We've touched on it a little, but let's explain why we only recommend buying certified diamonds. Certified diamonds are more expensive than uncertified diamonds, but diamond certification ensures that you've received the diamond quality you've paid for.

    gia report

    The American Gem Society is the other acceptable grading authority. They grade like the GIA, but their main difference is they grade the AGS Ideal 0 as their Excellent Cut. An Excellent Cut graded diamond from the GIA is the same as an ideal cut diamond, but the GIA just doesn't use that terminology. 

    In short, diamond certifications are a guarantee that a retailer is selling you the right quality diamond for the right price. You'll frequently find "independently certified" or GSI certified diamonds in brick and mortar retailers.

     These retailers use these agencies because they're much cheaper in bulk rather than getting it done at the GIA or AGS. They'll also sell GIA certified diamond engagement rings for more than you'd get them at an online retailer, because it costs the company more. 

    Read also: Where to Buy GIA Certified Diamonds

    How To Get The Best Deal When Buying Radiant Cut Diamonds Online?

    I've touched on a number of different ways and benefits that will help you when buying radiant cut diamonds online. Here's a quick recap of Radiant Cut Diamonds 101. 

    • Choose a retailer with a clear 360˚ viewer
    • Choose a retailer with a large selection
    • Only buy GIA or AGS certified natural diamonds. For lab diamonds, buy GIA, IGI, or GCAL 
    • Choose a retailer with a warranty that covers routine maintenance like retipping prongs or rhodium plating. 
    • Choose a retailer with a good return policy and easy process
    • Remember that radiant cut diamonds show color more, so make sure to choose higher color grades.
    • Remember that radiant cut diamonds hide inclusions more  so they don't need higher clarity grades. 
    • Make sure your cut corners are even

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