A Guide To Asscher Cut Diamonds

The distinctive Asscher cut diamond is a variation of the emerald cut featuring a square step-cut facet arrangement with relatively wide corners. This cut was developed in the early 1900’s by Dutch diamond cutter Joseph Asscher and became extremely popular in the Art Deco period of the 1920’s and 1930’s. The design of the original Asscher cut is not protected by patent and many cutters today produce this popular step cut. The Asscher family later modified the original design by adding 16 facets and received a new patent calling it the Royal Asscher™. GIA laboratory reports refer to the now generic original design as a “square emerald cut”. It is sometimes referred to more literally as a ‘square octagonal step cut’. The following article is primarily based on natural diamonds, but much of this information is also applicable to the asscher cut lab created diamonds which have entered the market.
Click below to navigate to a specific section of this article:

What is an Asscher Cut Diamond?

The symmetry of the square pattern gives Asscher cut diamonds a unique visual appeal. The facets running from the corners on both the crown and pavilion create a pattern often referred to as the “windmill”. This pattern is important to the overall visual quality of the Asscher cut and should be distinct, symmetrical, and balanced – not too thick and not too thin. The step facets need to have adequate difference in angles between them so that they are distinct and do not merge into one another. In such a case, scintillation is diminished.
Assher Diamond Facets Table
GIA2208157567 Diamond
Asscher Diamond Facets Pavilion
The asscher cut – facet diagrams and actual photo
Asscher Diamond Facets Windmill
The windmill pattern seen in the asscher cut diamond facets
From an outward shape perspective an Asscher cut diamond resembles a square radiant cut, with both cuts sharing an octagonal outline. The shape is also similar to the princess cut and some cushion cuts. But from a light performance standpoint the Asscher has a distinct flavor. The princess has pointed corners and a brilliant style facet arrangement causing it to have an entirely different visual appearance in terms of fire, brilliance and scintillation. Radiants and cushions likewise have mixed facet arrangements that are completely dissimilar to the horizontal step-like facets of the Asscher.
There are 3 rows of 8 facets on the crown and pavilion, and the girdle consists of 8 facets. Counting the table facet, the Asscher therefore consists of 57 facets. If the culet also has a facet, the total is 58.

Certification of Asscher Cut Diamonds

Most Asscher cuts on the market will be offered with a GIA report. Unfortunately, GIA does not grade overall cut quality on any but round diamonds. While AGS Laboratories does offer a light performance based report that grades cut quality on Asschers, most cutters avoid the extra time and weight loss required to cut to AGS Ideal parameters, and instead send their Asschers and other fancy shapes to GIA. The GIA report is trusted by consumers all over the world and the document will not punish a cutter for taking some liberties with cut quality.
GIA-2208157567 Certificate
Click to enlarge
Because you are not likely to find a certified Asscher on the market with meaningful cut analysis, working with a vendor who supplies both HD video and advanced light performance images is crucial to finding a high quality Asscher cut diamond.

Light Performance

Square emerald cuts like the generic Asscher are characterized by a type of light performance that is distinctive from the brilliant style facet arrangement of cuts like the round brilliant, princess, oval and other brilliant variations. This derives mainly from the orientation of the pavilion facets. Brilliant styles have vertical facets and step cuts have horizontal facets. The horizontal “step” facets return to the eye large flashes of light that move relatively slowly, as opposed to the rapid scintillation of the brilliant styles.
In addition to this distinctive optics of the Asscher, there are of course differences between individual Assher cuts in terms of overall light performance. Brightness is impacted by cut quality, and since step cuts in general do not display as much brightness as a precision cut brilliant such as an Ideal or Super Ideal cut, it is important to evaluate this key factor. The best way to do that is with ASET (Angular Spectrum Evaluation Tool), in combination with photos and videos.
ASET is the graphical tool at the center of the light performance based cut quality analysis system developed by the American Gem Society Laboratory (AGSL). An ASET light map will reveal important things about how a diamond is handling light, and by comparing the light maps of different stones, it is possible to identify candidates that are brighter and have better contrast patterns than others. This will aid in selecting a diamond that will be more consistently beautiful in a wider range of lighting conditions.

ASET Signatures for Asscher Cut Diamonds

Below are examples of ASET light maps for Asscher cuts alongside their actual photos. All are well cut diamonds, but there are clear differences in how they are handling light. Below each set of images is a brief summary of the characteristics its ASET signature reveals.
GIA1359129497 ASET
GIA1359129497 Diamond
Outstanding brightness conveyed by copious amounts of Red. Minimal contrast (blue) that will suppress some scintillation.
GIA2277430908 ASET
GIA2277430908 Diamond
High percentage of green and some light leakage suggests lower than optimal brightness.
GIA2208157567 ASET
GIA2208157567 Diamond
Extremely bright but with some leakage in the culet area. Windmills are dynamic producing good scintillation.
GIA6255754404 ASET
GIA6255754404 Diamond
Good proportions of red, green and blue, but not optimally distributed. Windmill are a bit weak. What the stone lacks in scintillation it makes up for in brightness.

Generic Asscher and Other Square Step Cuts

In addition to the original Asscher configuration which is now generic, there are other versions that have been developed over the years. The descendants of Joseph Asscher are still in the diamond business and have created a 74 facet version of the original that they have been granted a patent on.
Another proprietary variation is known as the Octavia™ cut. The Octavia is unique in that it features a higher crown and smaller table than the Asscher. The developers explain that their design increases the number of virtual facets, most of which are medium in size, resulting in better brightness and scintillation than the generic Asscher. The Royal Asscher featuring an additional 16 facets accomplishes something similar. The generic Asscher is characterized by fewer and larger virtual facets.
Asscher Cut Diamond

Asscher Cut and Color Grade

Because Asscher cuts are relatively deep they tend to show more color that round brilliants. But because they are more symmetrical than rectangular emerald cuts, they do not tend to concentrate color in their ends the way emerald cuts sometimes do. Being a step cut like an emerald, the volume of light returning to the eye that can mask body color is not as great as a well cut round.
The Asscher cut therefore handles body color somewhat better than an emerald cut and it is not necessary to buy up in color grade to avoid seeing too much body color. But if you are on the fence about your color preference and you choose an Asscher, it is still prudent to err on the side of the higher color.

Asscher Cut and Clarity Grade

Step cuts have longer and slower scintillation due to their long horizontal facets. And, in the case of emerald cuts the table facet is larger providing a bigger window into the stone to be able to see inclusions. But Asscher cuts produce more and smaller virtual facets and they tend to have smaller tables. Therefore, an Asscher cut conceals inclusions better than rectangular emerald cuts, though not as well as brilliant style facet arrangements.
It is therefore recommended to shop for somewhat higher clarity grades than what might be your tolerance in a round brilliant. VS is a good baseline clarity area for Asschers, though it is still possible to find nice stones in the SI range.

Carat Weight vs Dimensional Size of Asscher Cuts

Asscher cut diamonds tend to have small tables, built up crowns, thick girdles, pavilion bulge, and excessive depth percentage. One or more of these characteristics can lead to the stone having a very small spread. With much of the carat weight hiding in these features, the outer dimensions and the apparent size make the Asscher visually smaller than other shapes. Even well cut Asschers will appear noticeably smaller than a well cut round brilliant. A one carat Asscher has an outer dimension in the 5.5mm range whereas an ideal round brilliant is about 6.5mm.

Asscher Cut vs Princess

Shoppers interested in Asscher cut diamonds are well advised to also consider the princess cut. It too has a square outline and works well in geometric designs with straight lines. Unlike the Asscher the princess cut features a brilliant cut faceting style and delivers more sparkle and scintillation.
Although square in shape, the princes does not have an octagonal outline as its corners come to points. And the flavor of the princess is altogether different than the Asscher in terms of light performance – more like that of the round brilliant. Shoppers looking for maximum sparkle from a square shape will not find a better alternative to a well cut princess, and as one of the most popular diamond shapes, the market provides far more princess cut options to choose from.
AGS Ideal cut princess are available in the market, and the A CUT ABOVE® Princess is a true super ideal. Shoppers looking for optimal light performance, therefore, have ready options in a square cut diamond.
A CUT ABOVE Princess Diamonds

Asscher Cut vs Radiant

Another option for shoppers interested in square shape diamonds is the radiant cut. Like the asscher cut, the radiant features an octagonal outline, typically with slightly smaller corners. Unlike the Asscher most radiants feature a mixed cut style and have much more scintillation than the Assher cut. Radiants vary in terms of their specific facet structure giving rise to different flavors of light performance. Some radiant cuts have a more brilliant style while others have more of a ‘crushed ice’ look.

Asscher Cut vs Round Brilliant

Apart from the distinctive difference in visual characteristics between the square step cut and brilliant style facet arrangements in terms of brightness and scintillation, there is also a pretty significant size difference. Because Asschers tend to be cut deep, the outer dimensions are generally much smaller than a well cut round brilliant. A one carat Asscher might have dimensions in the range of 5.5 mm whereas an Ideal cut round is closer to 6.5mm.
Adding to this differential is the fact that Asscher cuts do not always have the edge-to-edge brightness that an ideal cut round brilliant has. This impacts their apparent size in a way that makes an Asscher cut diamond look quite a bit smaller than a nice round brilliant. It is therefore necessary for shoppers to ‘buy up’ to higher carat weight in order to achieve the same look as a round in terms of visual size.
For the ultimate in light performance, brilliance and fire consider the internationally acclaimed A CUT ABOVE® Hearts and Arrows. With complete edge-to-edge brightness, these precision cut diamonds deliver elite performance and extreme sparkle.

Asscher Cut Lab Created Diamonds

One of the biggest events in the diamond industry, maybe in its history, is the emergence of lab grown diamonds in gem quality and larger sizes. While synthetic diamonds were first successfully grown in the 1950s, they have been largely relegated to the abrasives industry until relatively recently. Today, lab created diamonds offer an increasingly popular option to natural diamonds because of their affordability. Lab created diamonds are real diamonds with essentially the same chemical, physical and optical properties of natural diamonds. Therefore, if cut with precision, they can be just as beautiful and durable as natural diamonds.
Asscher cut lab created diamonds can be evaluated in terms of their cut quality and performance according to the same criteria as presented in this article. But there are some important considerations and they can be understood by reviewing our guide to lab grown diamonds.
Because of their affordability many shoppers are choosing lab diamonds in a greater range of shapes and facet arrangements than ever before, and adding diversity to their diamond collections. An Asscher cut lab created diamond is becoming an ever more popular choice for its distinctive character and beauty.

Asscher Cut Diamond Engagement Rings

With the resurgence in interest in vintage styling, it is no surprise that the diamond darling of the Art Deco Period would have a new day in the sun. With antique designs getting strong play in the last decade or so, the Assher cut has gained renewed popularity. Designer like Tacori and Verragio whose artistic and ornate designs harken back to an era where highly detailed design elements are celebrated, the Asscher cut has found a new generation of admirers.
But an Asscher cut diamond can also make an eye-catching statement even in a more modern setting with little embellishment. For an especially distinctive diamond, its versatility is pretty remarkable. The style range and the number of ways an Asscher cut diamond engagement ring can be set is limited only by one’s imagination. For some shoppers, choosing a lab created Asscher is a beautiful way to acquire an awesome designer setting while staying within a reasonable overall budget.
Ritani 1RAZ1013 Tapered Baguette Diamond Ring
Ritani 1RAZ1013 Tapered Baguette Diamond Ring
Valoria Flora Twist Diamond Engagement Ring
Valoria Flora Twist Diamond Engagement Ring
A. Jaffe MES751A Diamond Engagement Ring
A. Jaffe MES751A Diamond Engagement Ring

Pros and Cons of Asscher Cut Diamonds

Like most fancy cuts, especially highly distinctive ones, the Assher cut may not be for everyone. Here are some pros and cons to help you determine if this unique diamond cut is for you.
  • Unique and distinctive. Draws interest and attention.
  • A well cut Asscher is among the brightest of the step cuts
  • More subtle light performance featuring slower but bolder flashes
  • Stylistically compatible with vintage designs
  • Step cuts are not as sparkly as brilliant style faceting
  • They look smaller than round brilliant diamonds
  • There are fewer Asscher cut diamonds in the market to choose from
  • Finding a well cut Asscher requires expert analysis

Asscher Cut Buying Tips

  • Make cut quality your priority
  • Avoid excessive depth. It is common to find Asschers with depth in the 80% range. They will look very small for their carat weight
  • Avoid extremely thick girdles. This hides a lot of weight, especially combined with excess depth percentage.
  • Look for ‘Windmills’ that are balanced in size and symmetrical in shape
  • Focus on I color and above, VS2 clarity and above
  • Deal with a merchant who has expertise in evaluating fancy shape diamonds.

Why Whiteflash

While Whiteflash is known for the super ideal cut round and princess diamonds we stock and keep in inventory, we offer our Other Diamond Category to customers looking for other shapes. Because our expertise is in light performance and the diamonds we stock are so carefully analyzed, we are well positioned to help customers find top performing, high quality certified diamonds of all shapes, in natural as well as lab grown. Our process involves the same attention to detail that we are known for in evaluating our in-house diamonds, including advanced light performance imaging. And because we are authorized distributors for all of the leading designer brands, our capabilities in producing an impeccable finished piece is second to none.
Our GIA and AGS credentialed diamond and jewelry consultants work with customers from all over the world, finding just the right diamonds and just the right settings for their needs. They do not work on commission – their sole objective is to deliver a brilliant experience to Whiteflash customers. You can have full confidence that you are dealing with a great company, and that you have a dedicated consultant who is an advocate for you from start to beautiful finish.

Be Inspired By Our Designer Engagement Rings

Find the perfect Designer Ring for your special diamond by clicking the links below, and let us build the ultimate ring for the love of your life!