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If you’re looking at super ideal cut diamonds, you already know that cut quality plays the most important role in a diamond’s beauty. But is a high cut-quality diamond worth the extra cost? Learn the difference between these top-cut diamonds and more typical excellent-cut diamonds, then decide for yourself. [Reading time: 6 min]
excellent cut diamond engagement ring

A diamond doesn’t need to be super ideal to look great. © CustomMade. Used with permission.

Whether or not you decide on a super ideal cut diamond, it’s important to examine your diamond up-close before you buy. If you’re shopping at a brick-and-mortar store, make sure the jeweler shows you the diamond under magnification from different angles.

If you’re shopping online, you must watch magnified videos of diamonds. It’s really the only way to ensure your diamond will have good performance, color, and clarity. James Allen’s True Hearts™ collection and Blue Nile’s Astor diamonds both offer amazing stones, and you can examine them all via closeup videos. These vendors make great places to start your online search for super ideal cut diamonds.

Going custom is another great option. A jeweler like CustomMade can help you find the diamond with the best cut and set it in a unique ring that will be absolutely stunning.

What is a Super Ideal Cut Diamond?

Super ideal cut diamonds have cuts with an extremely high degree of precision and angles that give them superior performance. The cut quality of a super ideal cut diamond goes above and beyond that of the GIA’s “Excellent” and AGS’s “Ideal” grades. It also means that the diamond will sell at a premium.

Diamond Proportions: Looking at the Numbers

Ultimately, angles and proportions are what give a super ideal cut diamond the best performance. However, evaluating these properties can become very complicated, very quickly.

For example, if you’re considering a diamond with an “Excellent” or “Ideal” cut grade, you’ll want numbers that place the stone in the mid-range of the grade. In other words, you don’t want a diamond that’s on the border between “Excellent” and “Very Good” cut grades.

Here’s where it gets tricky. Many factors contribute to a diamond’s cut grade. The total depth, table percentage, crown heightpavilion depth, and the angles of the crown and pavilion all have to work together nicely. As you can imagine, this doesn’t fit nicely into a little table. There are just too many variables.

So, unless you have a degree in optics, it’s probably easier to learn to judge the diamond’s visual performance rather than the numbers.

Judging Performance

In the end, a super ideal cut diamond is only worthwhile if it has superior performance. A diamond with a particularly amazing cut will have better sparkle and will actually appear larger than one with an inferior cut.

However, if you can’t tell the difference between the performance of an Excellent-cut diamond and a super ideal cut diamond, there’s really no reason to pay more. Simply put, the GIA “Excellent” or AGS “Ideal” cut grades will suffice for most buyers. Judging a diamond’s performance beyond that requires some expertise and a good eye.

Take a look at the videos of these two James Allen diamonds: one excellent cut and one True Hearts™.

Compare them side by side at James Allen.

There’s no big difference in performance between these two diamonds, but one costs $1,110 more than the other.

So, let’s discuss “diamond performance” and the easiest ways to evaluate it.

Brilliance, Fire, and Sparkle

The three factors of diamond performance are brilliance, dispersion, and scintillation. Brilliance refers to the white light you see. Dispersion, or “fire,” refers to the colored light. Scintillation is the pattern of dark and light areas that “sparkle” as you move the diamond.

For example, compare these two diamonds from James Allen’s True Hearts™ collection. This 1.02-ct diamond has a good balance of brilliance and fire, while this 1.04-ct one has much more fire. (You’ll need to watch the videos to appreciate these effects). They both have great cuts. Choosing one over the other would be mostly a matter of preference.

Brilliance, fire, and sparkle are all important to a diamond’s performance, and the diamonds with the best cuts will show more of these effects. Nevertheless, differentiating the very top super ideal cut diamonds from standard “Excellent” or “Ideal” cut diamonds is difficult.

Different types of imaging — such as Hearts and Arrows, Idealscope, and ASET — can really help you evaluate a diamond’s quality. These will give you a better idea of the diamond’s symmetry and light return.

Symmetry: Hearts and Arrows

You’re probably familiar with “Hearts and Arrows,” but you may not know how to evaluate them. In a perfectly symmetrical, well-cut diamond, a Hearts-and-Arrows viewer will show a symmetrical pattern of arrows from the face-up view of the diamond and hearts from the face-down view.

However, simply seeing hearts and arrows isn’t enough. The patterns should be perfectly symmetrical in a super ideal cut diamond, but most dealers will still use the designation “Hearts and Arrows” for less perfectly symmetrical diamonds.

Take a look at the hearts pattern from this James Allen diamond. It shows some asymmetry. Look closely at the V-shapes in the center.

hearts pattern - super ideal cut diamond

© James Allen. Used with permission.

Even though the pattern isn’t perfect, this is still a nice diamond. That’s because even though hearts and arrows show up in top-cut diamonds, their presence alone doesn’t indicate high quality. Their imperfection doesn’t necessarily indicate poor quality, either. Some diamonds with imperfect hearts and arrows have better performance than some with a perfect pattern.

ASET and Idealscope Imaging

ASET and Idealscope provide similar imaging. Both provide a view of the diamond’s light return and light leakage.

The simpler tool, the Idealscope shows areas of red, white, and black. Red areas show light return, while white areas reveal light leakage. Black areas are simply where the camera blocks the light and indicate areas of light return from a straight-on view. With Idealscope imaging, try to find stones with minimal white areas.

The Angular Spectrum Evaluation Tool (ASET) uses more colors than the Idealscope to indicate light return from different angles. Blue areas are important for contrast and should match up with the “arrows” pattern, which would be black in an Idealscope. Green indicates light return from low angles, while red, the most important color in an ASET, shows strong light return at medium angles. White and black both indicate light leakage. With ASET imaging, look for stones with minimal white and black areas.

Buying a Super Ideal Cut Diamond

Ultimately, if you pay more for superior cut-quality, you should get superior cut-quality. Although many brand names claim to offer this, they ultimately fall short of the mark.

So, the only way to know that you’re getting something superior is to look at the diamond yourself. Comparing performance between different diamonds and assessing ASET, Idealscope, and hearts-and-arrows images take time, patience, and an eye for detail.

If you’re set on a super ideal cut diamond, be sure to take the time to buy smart.

Our Recommendations

In the end, the quality difference between a super ideal cut diamond and a GIA “Excellent” or AGS “Ideal” is marginal. Although a top cut will make the diamond appear somewhat larger, the higher cost might not be worthwhile. Instead, you could just as easily put that money toward a higher carat diamond.

We recommend shopping for an excellent or ideal-cut diamond. Limit your search to diamonds with a table of 54 to 57% and a depth of 59 to 62.5%. When shopping online at James Allen and Blue Nile, you can limit your searches to these parameters. The cut grades will always show up on the grading reports. Then, just make sure your diamond has a nice sparkle when you view the video!

Of course, seeking expert help is always a great option. Jewelers like CustomMade can help you through the entire process and create the perfect ring to match your ideal diamond.