Cushion Cut Diamond: Buying Guide & Expert Insights

Cushion Cut Diamond: Buying Guide & Expert Insights

Cushion Cut Diamond: Buying Guide & Expert Insights

Posted by Sharif Khan on 12th Jan 2021

Key Takeaways:

  • Cushion cut diamonds have been around for a couple of centuries, and because of innovation in cutting methods, this beautiful shape is increasingly becoming more popular. 
  • There are three types of cushion cut diamonds: cushion brilliant (traditional ones), cushion modified (has crashed iced faceting), and a hybrid of the two (combining the brilliance of both and a popular option). See more below.
  • In terms of the cut, a table of 58-68% and a depth of 57%-69% is good. See the chart below for more precise numbers.  
  • In terms of length-width ratio, a ratio of 1-1.05 is recommended for square and a ratio of 1.15-1.30 is recommended for a rectangular cushion cut, depending on how elongated you want the stone to look. See details below.
  • In terms of prioritizing the 4Cs, if you want to buy a high quality diamond (investment grade) in a given carat range, go for something like this (option 1). If you want to maximize on the carat weight without compromising on quality either, go for an option like this (option 2). If you don't mind compromising slightly on cut, color and clarity in order to maximize on carat weight, consider an option like this (option 3). Finally, if you want to compromise on one C to maximize on the other 3Cs, compromise on color and maximize on carat weight, cut, and clarity (option 4). These four scenarios are explained below in detail.  
  • Buy a diamond that is either graded by GIA or AGS.
  • Here is the list of our top online sites for diamonds and engagement rings to consider.  

Overview Cushion Cut:

For the first century of its existence, this 200 year old diamond cut with a shape of pillow was the most popular diamond shape of its time. It became a de facto diamond shape in the early 20th century. Cushion cut diamonds collate the square cut with round corners; it is a classic cut and meets the standards of individuals who like the combination of square and round shape diamonds.

Cushion Brilliant Cut diamonds were originally instigated by Marcel Tolkowsky during the 1920’s when he was doing research on different cuts of diamonds. Overtime, the cushion cut diamonds went trough some conspicuous changes such as smaller culet, larger table, and an improvement in its brilliance. These refinements attracted many buyers because it made the cushion cut diamonds to have an antique yet a modern look.

Cushion Brilliant vs Cushion Modified Brilliant Cut Diamonds:

Cushion Brilliant vs Modified

The modified cushion cut diamond is basically an alternative version of the original cut with modern variation to keep up with the style as well as the demand of buyers. A modified cushion diamond tends to have a “crushed ice” or a “needle” like facet pattern. They contain an extra row of facets below the girdle, and the facets on the pavilion do not reach the girdle. It possesses a sparkle that is analogous to sparkling water. One benefit of this shape is that diamond cutters save more carat weight than in traditional cushion brilliant cut diamonds hence making it a more economical diamond. The demand for modified cushion cut diamonds is low which also effects its price. When you look through the table of a modified cushion cut diamond, you won’t be able to find faceting in it unlike the standard cushion cut diamonds. Therefore, there is a significant difference in the look of the standard cushion cut and the modified one. A modified one would have radiant/crushed iced sparkle unlike the standard one.

Cushion Modified Brilliant Difference

A hybrid cushion cut is recently introduced where cutters tries to achieve the roundish brilliance of the standard cushion count while also saving on the carat weight by using the cutting technique of the modified cushion cut. This cut contains four pavilion facets which extends from the center towards the girdle just like in standard cushion brilliant cuts, but with modified facets between them like in the modified version.

Cushion Modified Brilliant Cut Hybrid

There are many standards that buyers should consider before buying a cushion cut diamond. But, personal taste will always dictate the choice. Cushion cut diamonds have great fire (the light that is reflected out of a diamond in a rainbow of color). Please follow the following guide for determining the quality of either the standard or modified cushion cut diamond.

Analyzing Cushion Cut:

Use the chart below to serve as a general guideline for you when evaluating the different aspects cushion cut shape.

Tools like JamesAllen's 40X Magnified 3D 360 Degree Video Technology can be very helpful in assessing how cushion cut diamonds defer from cushion modified brilliant cut diamonds. It can also help you assess length to width ratios to determine what might be optimal ratio that you like. Try to play with their search filter to get a better sense what would be ideal. 

Depth %
  • Poor/Far: <55 or >73.1 / 54-56 or 71-73
  • Good: 56-58 / 70-71.1
  • Very Good: 58-61/67.3-69.9
  • Excellent: 61.1-67
  • Table %
  • Poor/Fair:<54 or >73.1/ 54-56 or 71-73
  • Good: 56-57.2/71.3
  • Very Good: 58-60.1/68.2-70.4
  • Excellent: 61-67.9
  • Culet
  • Poor/Fair: Very Large/Large
  • Good: Slightly large
  • Very Good: Medium/Very Small
  • Excellent: None
  • Girdle
  • Poor/Fair: Ex. Thin – Ex. Thick
  • Good: Very thin - thick
  • Very Good: Very thin - slightly thick
  • Excellent: Thin - slightly thick
  • James Allen

    Most of the time, cushion diamond cuts are sold in square shape with a length to width ratio of 1.00, but these luminous diamonds also come in rectangular shapes. If you are looking for a popular cut, buy a cushion diamond that is slightly rectangular in shape. The length to width ratio of that choice should be 1.10-1.21.

    The chart below should be a nice a guide to help you to evaluate the length to width aspect of cushion cut diamonds.

  • Poor/Far: >1.09 / 1.06-1.09
  • Good: 1.04-1.06
  • Very Good: 1.00-1.04
  • Excellent: 1.00-1.03
  • Rectangle
  • Poor/Fair:<1.09/1.52
  • Good: 1.09-1.16 / 1.22-1.31
  • Very Good: 1.09-1.16 / 1.22-1.31
  • Excellent: 1.16-1.22
  • square vs rectangular cushion cut

    Evaluating Color:

    Color in cushion cut diamond diamonds is an important factor. Since its a brilliant cut with many  facets, you might be able to compromise slightly on color without losing on the brilliance of the stone. While colorless diamonds are always great (color should be second priority after cut), you may also go for G, H, I colors. G is as good as colorless, H is a fantastic sweet spot for people with budget constraints whereas I becomes slightly tint (barely noticeable). 

    For detailed information on the color of cushion cut diamond, use the table below

    < 0.50 Carat
  • Poor/Far: >M/ L-M
  • Good: I-K
  • Very Good: G-I
  • Excellent: D-G
  • 0.51 – 1.0 Carat
  • Poor/Fair: J-K / >L
  • Good: I
  • Very Good: H
  • Excellent: D-G
  • 1.0 – 2.0 Carat
  • Poor/Fair: H-I / >I
  • Good: G
  • Very Good: D-F
  • Excellent: D-F
  • >2.0 Carat
  • Poor/Fair: H-I / >I
  • Good: G-H
  • Very Good: D-F
  • Excellent: D-F
  • Choosing Clarity:

    Choose a cushion cut diamond that meets your standards in terms of clarity. Each of our customers has a unique standard for clarity and color. Some of our customers want a flawless diamond with a lot of clarity, while others are perfectly comfortable with a slight inclusion as long as it is not easily noticed. GIA provides excellent help with their clarity grades, so you can use it to choose an oval cut diamond that will meet your standards. The chart below serves as a general guide for you to evaluate clarity in oval diamonds.

    < 0.50 Carat
  • Poor/Far: I2 / >I2
  • Good: I1-I2
  • Very Good: VS2-S12
  • Excellent: FL-VS1
  • 0.51 – 1.0 Carat
  • Poor/Fair: I2 / >I2
  • Good: SI2
  • Very Good: VS2-SI2
  • Excellent: FL-VS1
  • 1.0 – 2.0 Carat
  • Poor/Fair: SI2-I1 / >I1
  • Good: SI1-SI2
  • Very Good: WS2-VS2
  • Excellent: FL-VS1
  • >2.0 Carat
  • Poor/Fair: >SI2
  • Good: SI1-SI2
  • Very Good: VS1-SI1
  • Excellent: FL-WS2
  • Four Scenarios to Consider While Buying Cushion Cut Diamonds:

    Over the last decade, here are the four scenarios that we have seen people consider when deciding what option is best for them in a given range while buying a diamond and how to compromise on the 4Cs of a diamond.

    Scenario One: Going for the highest quality in a given carat range – Quality is preferred over size. Investment grade diamonds

    Under this option, buyers go for the highest quality diamonds. Since such diamonds are extremely rare and most probably within 1% of all diamonds mined, they are considered investment grade diamonds. These would be Flawless to VS1 clarity, D-F color, Excellent Cut, GIA/AGS graded diamonds with no fluorescence and at least 1 carat in weight.

    Scenario Two: Prioritizing a balanced-approached, getting the best of all 4Cs. Both quality and size is a priority in this range

    In this option, shopper aims to maximize on both size and quality. We still consider diamonds in this range as investment grade as these diamonds are high in demand because most buyers can afford them as opposed to the highest quality ones. The range that would qualify under this range would be up to SI1 clarity, H color, excellent to very good cut with excellent proportions, and up to medium blue fluorescence. Shoppers still prefer either GIA or AGS graded diamonds in this range.

    Scenario Three: Compromising on all other 3Cs in order to maximize on the carat weight. Quality is still a priority to a degree

    Under this option, the buyer basically aims for a large diamond within his/her budget, but also wants a nice looking diamond that is preferably eye clean. So what they would do is to go as low as SI2 clarity, up to J color, very good to excellent cut, and up to strong blue fluorescence. If you go for this scenario, just buy GIA graded diamonds. We have seen other labs, including AGS, play games in lower clarity grades, especially when it comes to clarity.

    Scenario Four: Giving up on one C entirely in order to maximize on other 3Cs because of a low budget

    Under this scenario, the buyer basically decides to give up on one C in order to get a big stone that is very strong in the other 3Cs. We would recommend that you give up on color in this option and maximize on clarity and cut. While a stone with big inclusions can affect the brilliance of a diamond significantly, a slight yellow hue or tint does not have that degree of an effect on the fire, scintillation and brilliance of a diamond. In fact, some shoppers actually prefer warmer colors such as J to M range. IF you go for this option, and if the stone is in the VS range, going for IGI or HRD graded diamonds is also a good idea. They don’t have big incentives to misgrade such color range stones. 

    Suggested carat weight, cut, color and clarity of Cushion Cut Diamond for people with budget constraints:

    Excellent Choice:

    • At least 1.0 carats in Weight
    • Very Good to Excellent Polish and Symmetry
    • G or above in color
    • SI1 or above in clarity
    • No Florescence
    • Length/width ratios: 1.0 -1.05 for square or 1.12-1.30 for rectangular shape

    Very Good Choice:

    • At least 0.90 carats in Weight
    • Good to Excellent Polish and Symmetry
    • H or above in Color
    • SI1 or above in Clarity
    • None, faint or medium blue florescence
    • Length/width ratios: 1.0 -1.05 for square or 1.12-1.30 for rectangular shape

    Good Choice

    • At least 0.80 Carats in Weight
    • Good to Very Good Polish and Symmetry
    • I or above in Color
    • SI1 or above in Clarity
    • None, faint or medium blue florescence
    • Length/width ratios: 1.0 -1.05 for square or 1.12-1.30 for rectangular shape

    Frequently asked questions about Cushion Cut Diamond:

    Are questions cut diamonds popular?

    Yes, after round and oval cut diamonds, we would say cushion cut diamonds are among the top sellers. Cushion cut diamonds have beautiful facets and a unique look to them. You cannot go wrong with cushion cut. However, if you are not sure about its shape or brilliance, we would recommend that you visit a look shop and compare them with round and other shape diamonds. 

    What are most popular among cushion cut diamonds between cushion brilliant, cushion modified, and cushion hybrid?

    By looking at the supply side of the diamond industry, we notice that a number of diamond dealers are increasingly cutting rough diamonds into the hybrid cushion cut. It suggests to us that these are very popular as it combines the best of cushion brilliant and cushion modified. It also sparkle more and has an elegant look to them. There must be high demand for the hybrid version hence more supply. 

    Why are cushion cut diamonds cheaper than round cut diamonds?

    They are not necessarily cheaper than round cut diamonds. What you have to understand is that it takes a bigger rough cut diamond to cut a 1 carat round diamond than it does to cut a 1 carat cushion cut diamond. The average diameter of a 1 carat round diamond is about 6.4mm while it is in the range of 5.4mm for square cushion cut diamonds. 

    Why are rectangular cushion cut diamonds more expensive than square cushion cut diamonds?

    Again, if you pay attention, the overall spread of rectangular cushion cut diamond is larger than that of a square cushion cut diamond which means a diamond has sacrifice a bigger rough diamond to cut a 1 carat rectangular cushion cut diamond than they would have to for a square cut. 

    Should I set a cushion cut diamond into a halo setting or plain solitaire?

    First, it depends on your taste. Second, if the stone is a small one (since cushion cut diamonds are generally small in overall spread), it is better to set them in halo settings so that it can be surrounded by other diamonds to give it a big look. 

    Recommended Proportions - Cushion Cut
    Depth% Table Girdle Cullet L/W Ratio
    60-68% 59-67% See Below None See below