By Gary A.
Edited by Brian M.
Published Oct 31, 2021
Edited on Dec 18, 2024
When it comes to choosing the right engagement ring, the brilliance and fire of a diamond cut can make all the difference in capturing the light and your heart.
Before we dive deeper into the specifics, here are some practical tips to help guide your decision-making process:
Now that youâve got these practical tips, use Jeweler AI below to find the perfect engagement ring that suits your style and budget:
It doesnât take an expert to know that diamonds do not come out of the ground looking the way they do by the time they make it to the jewelerâs table. What does take an expert, however, is recognizing the potential a rough diamond holds â and, of course, how to turn that potential into a reality.
Every diamond you come across during your search will have spent hours under a series of highly specialized tools capable of turning an unassuming, dull, and irregularly shaped stone into an impeccably proportioned, symmetrical and brilliant diamond ready to place on the finger of your future bride.
Nevertheless, just because a diamond has been cut and polished, thatâs not to say it’s worthy of your money. Diamond Cut is a complex subject, and one that it is absolutely essential to understand and consider before you make any commitments.
Cut refers to a number of interrelated features, such as proportion, symmetry, polish, and depth.
Any diamond shape, from the classic Round Brilliant to the highly modern Princess, needs to be cut to some pretty specific proportions in order to create a good light performance and, put simply, to look right. A poorly proportioned Round Brilliant, for instance, could look very squat or very narrow and, even if you donât consider yourself to be familiar with the diamond shapes, the flaws can be highly obvious.
Similarly, the process of polishing a diamond might leave some unsightly marks and flaws on the surface. The diamondâs face-up appearance might look âoffâ due to poor symmetry or an uneven shape, or it might appear dull and lifeless alongside other diamonds due to an oversized table.
All of these possibilities â and more â are addressed within the cut category, which happens to be the first of the Four Cs every jeweler wants you to understand before you make a decision.
One of the key reasons why Round Brilliant diamonds are as popular as they are is down to the fact that they offer more sparkle than any other diamond shape. They offer truly spellbinding light performances of fire, brilliance, and scintillation and, when cut to a high standard, will appear to come to life every time the light hits upon their surface.
The key ingredient there, however, is a high standard of cut. Not every Round Brilliant diamond created is cut well â but it is essential that every Round Brilliant diamond you consider is.
We wouldnât talk about the Four Cs as much as we do if any one of them were not important. Cut, color, clarity and carat are all going to be your top considerations throughout the diamond buying process, and none of them can afford to be relegated to the âDonât Worryâ pile. That said, clarity, color and carat weight all offer much more scope for buyers looking to find a beautiful diamond that fits with their budget. For instance, while VVS1 is considered the âidealâ for diamond jewelry, diamonds from the VS and SI grades can appear just as beautiful to the naked eye. Similarly, while D color diamonds canât be beaten on paper, they can be rivalled by diamonds with color grades as low as G, H, I and J.
Cut is a little less obliging. We will always recommend shoppers stick to the Excellent and Very Good grades, and never dip below since this can have a profound impact on the diamondâs sparkle and brightness
No, shape refers to the specific form a diamond is cut into. A few examples of this are the Round Brilliant, the Emerald, and the Cushion â although these are often referred to as the âdifferent diamond cuts.â
While the term âcutâ may be used interchangeably a lot of the time, it is often easy to tell the difference â primarily because cut is whatâs graded within the GIA Report, while shape is merely listed as one of the diamondâs key features.
Itâs also important to note that the diamondâs shape will affect how it is graded. While Round Brilliant diamonds are assigned a specific grade for cut, as well as separate grades for symmetry and polish, other diamond shapes are only assigned grades for those two features, and not a comprehensive cut grade.
The GIA studied 70,000 Round Brilliant diamonds in order to develop their methodology for assigning a cut grade to this popular shape.
When exploring diamond cuts, the terms “Ideal” and “Excellent” represent the highest standards of diamond cutting, showcasing the stone’s ability to reflect light with maximum brilliance and fire. An “Ideal” cut is often a term used by specific certifying bodies and brands to denote a cut that meets exacting standards beyond the typical “Excellent” rating given by the Gemological Institute of America (GIA). These diamonds are shaped with precise proportions and angles to optimize light return.
“Excellent” cut diamonds, the top grade in GIAâs system, also provide outstanding brilliance and sparkle but allow for slightly broader parameters. This makes them more widely available and slightly less expensive than the “Ideal” cuts. When choosing between an Ideal and an Excellent cut diamond, consider your budget and the level of brilliance you desire. Both cuts will serve as a stunning centerpiece to any engagement ring, ensuring the diamond captures every possible glint of light, but an Ideal cut offers that extra edge of perfection that might be worth the investment for those seeking the absolute best in diamond craftsmanship.
Round Brilliant diamonds are graded for cut quality on the following scale:
Excellent | Very Good | Good | Fair | Poor |
The most important thing to understand about this scale is that it covers a range of features concerning cut quality and that any Round Brilliant diamondâs cut grade is determined based on numerous components â not one single featureâ¦.
The subject of cut quality is predicated on seven factors including brilliance, scintillation and weight ratio, and the GIA takes all of these factors â and more â into account as they grade the cut quality of Round Brilliant diamonds.
Barring polish and symmetry, each of the seven factors involved in determining cut grade are noted down in order, before the lowest grade is picked out and used to determine the grade. If, for instance, the diamond receives a grade of Very Good for brightness, fire, scintillation, and weight ratio and a grade of Fair for durability, then the cut grade will be Fair.
However, if the diamond receives a grade of Excellent for brightness, fire, scintillation, weight ratio and durability, and a grade of Fair for polish and symmetry respectively, it will still be given an Excellent cut grade.
This is why itâs important to study the GIAâs full report and to know how to extrapolate the most relevant information from it.
Excellent and Very Good represent the best cut grades â and the only ones we would ever recommend our readers invest in.
Unlike clarity and color, cut offers very little leeway for buyers. Yes, you can save many thousands of dollars by turning to SI2 diamonds instead of VVS1 diamonds, or by shopping from the Near Colorless grades rather than the Colorless grades but, when it comes to cut, we would never recommend taking the same open-minded approach.
The main reason behind this is the fact that a poorly cut diamond wonât sparkle as it should â and weâre willing to bet that, for you, finding a sparkly diamond is pretty much synonymous with finding a good diamond.
Also, barring the fact that dull and lifeless diamonds just donât scream âromanceâ like the ultra-brilliant, ultra-fiery diamonds do, a poor cut can just look off. It doesnât take an expert to recognize a wonky circle â and, in a poorly cut diamond, thatâs exactly what you see each time you look down on it.
According to the GIA, an Excellent cut grade refers to diamonds with the highest levels of brilliance and fire, while a Very Good cut grade refers to diamonds that appear to offer just about as much brilliance and fire to the naked eye.
If you go any lower on the cut scale, youâll start to encounter a lot of diamonds with a lot less sparkle.
Brilliance refers to white flashes of light, while fire refers to the flashes of colored light that a diamond emits â a beautiful complement to the stark, white brilliance created across the diamondâs surface.
Some people have a preference for fire or brilliance, and some cuts will offer more of one than the other. For instance, the Cushion shape tends to create more fire than brilliance. The Round Brilliant, however, creates a stunning and largely even-handed combination of the two â another reason behind its lasting popularity.
Fire, like brilliance, is not guaranteed. Round Brilliant diamonds with a cut grade of Excellent or Very Good will be capable of producing more fire than those with a poor cut or asymmetries.
Not only is it made out of the hardest natural substance on the Mohs scale, but a Round Brilliant diamond features a pretty sturdy shape with no sharp corners like those found on the Princess cut and Marquise cut.
However, a poor cut can make a diamond far more vulnerable to some pretty major damage, and thatâs why the GIA take this â specifically, the strength offered by the girdle â into consideration when grading a Round Brilliant diamondâs cut.
The girdle is the widest part of the diamond, between the crown and the pavilion, where the facets of one are intended to line up with the facets of the other. While, away from the microscope, it may appear to come to a very sharp and precise point, this is actually considered less than ideal for a diamond of any shape, as these edges (or corners) can easily chip or crack.
An excellent Brilliant Round diamond will feature a girdle of Thin to Slightly Thick. An extremely thin girdle is simply undesirable, and the sign of a poor cut lacking vital durability.
Thereâs no one way to choose a good diamond through its cut quality. Youâll have a certain amount of wiggle room for finding a good and reasonably priced diamond â just not as much as you have for color or clarity.
GIA graders use a pretty complicated equation based on the diamondâs weight and average girdle diameter.
The most important thing to understand about this aspect is that no matter the diamondâs carat weight, it should always appear to represent its actual weight.
The easiest way to understand this is to consider the importance of a diamondâs face-up appearance â or, more specifically, what you see when you look straight down at the diamondâs table and crown. Since this is the part of the diamond youâll be looking at when itâs set within a ring, it stands to reason that itâs the most important part â and not least of all because this is where most light is supposed to enter and exit the diamond for maximum sparkle.
A 3 carat diamond wonât be worth much if an overwhelming proportion of its weight is held in its lower half â the pavilion â rather than its face-up appearance. For all its extra weight, it simply wonât appear anywhere near as big as other 3 carat diamonds with better weight ratios â and wonât achieve a great sparkle, either.
For these reasons, itâs no surprise that we would never recommend anyone opt for a diamond with a weight ratio graded below âVery Good.â
There is no single âidealâ proportion. This is the same for every diamond shape â and the reason why the ideal cut proportions we have given refer to ranges â and sometimes multiple ranges, depending on the shape â rather than specific numbers.
This is why the GIA – and us at WillYou.com – recommend that you take a close look at the diamondâs specific measurements, and hold them up to the recommended ranges for that shape, as well as paying attention to the diamondâs cut grade.
Only by looking at both elements on the page â and, of course, the diamond in front of you â can you be sure youâre making a strong decision.
This refers to the arrangement, sizes, angles, and number of facets found on a diamondâs surface. Unlike cut, a symmetry grade is given to every diamond graded by the GIA â not just Round Brilliants. Across the surface of a diamond with Excellent symmetry, you will notice an even display of fire and brilliance. Errors can easily lead to one side being brighter than the other.
Symmetry is graded using the same scale used to grade cut, which runs from Excellent and Very Good through Good, Fair and Poor.
A diamondâs facets are the reason it is able to sparkle the way it does. Each one is angled slightly differently to the facets on either side and, together, they ensure that a diamond is able to refract and reflect light in a way that generates a captivating light performance.
Itâs very important to sparkle but, as with cut, you can afford to step down to the Very Good grade rather than focusing exclusively on the Excellent cut grade.
Symmetry is arguably more important than polish â although a good polish grade also remains essential to the diamondâs beauty and sparkle â and should never be sacrificed for the sake of a lower price.
The importance of sparkle is so central to a diamondâs value that, as with cut, poor symmetry can drag down a diamondâs price substantially â typically by around 10% â 15%. As with cut, this is not an area to attempt to save money, as any savings will be reflected in the face-up beauty of the diamond.
You can read our full guide to diamond symmetry here.
Polishing represents one of the final steps behind the creation of any diamond, and ensures a smooth, glassy, mirror-like finish to the diamondâs facets, as well as an even sheen across its entire surface â provided itâs done to a high standard.
The process is a little more involved than it may sound, with diamond polisher being required to hold the diamond against an abrasive disc to ensure that the facets are made as smooth and precise as possible. As a result, itâs relatively easy for the diamond to be marked, burned, or damaged.
Again, diamond polish is graded using the same scale used to grade Cut and Symmetry: Excellent, Very Good, Good, Fair and Poor.
As with many other of a diamondâs features, polish is examined under 10x magnification in order to identify any minor â or more significant â issues caused during this process.
These issues can vary from very slight abrasions during the ridges between facets â known as the facet junctions â or a vague, white âburn,â to more serious issues like scratches, draglines or a granular texture along the girdle.
Unfortunately, it is possible for these flaws to cause noticeable defects on otherwise attractive diamonds â and, in severe cases, to interrupt the diamondâs sparkle, particularly if the polishing issue is located on the table or crown of the diamond.
An unfortunate phenomenon known as the âbow tie effectâ is all too common in the elongated shapes of fancy cut diamonds, including the Pear, Marquise, and Oval. It presents as a dark ribbon or âbow tieâ across the center of the stone, which can at times be pretty difficult to ignore â a definitive dark spot within the stone.
Itâs important to keep in mind that not all bow ties are necessarily bad. Yes, it comes down to personal preference, but some âmilderâ bow ties can actually create a little extra depth within the stone that some buyers find desirable.
The more obvious bow ties are, however, a sign of poor cutting, and should be avoided.
In some Round Brilliant diamonds, an effect known as âhearts and arrowsâ can be achieved. In diamonds featuring this phenomenon, eight âarrowsâ can be seen across the table and crown of the diamond, and eight hearts can be seen around the pavilion when viewing the diamond upside down. It is important to note that this phenomenon can only be observed through a special viewer.
Diamonds have to feature a very precise cut in order to achieve this effect, and some cutters specifically cut their diamonds to achieve this effect.
While romantic, the high price given to hearts and arrows diamonds is generally considered an unnecessary one, since this pattern wonât be visible once the diamond is set within a ring and worn on the finger.
The diamondâs culet â or the very lowest point on the diamond, where the facets of the pavilion meet â is taken into account with regards to symmetry, as it can be off-center or out of alignment with the table. This is not the same as the diamondâs culet size, however.
While not included within the cut grade, the GIA does offer a grade for the culet, and this is found on the stoneâs proportion diagram within the report.
We have put together a full guide to the culet here. For now, itâs important to understand that culets can directly impact the face-up appearance of the diamond, and create the unwanted effect of a noticeable inclusion right in the center of the diamondâs table.
Ideally, any diamond you choose will feature no culet at all. This will be identified by the word âNoneâ at the base of the proportion diagram. Even a diamond that has been cut to a high standard in every other respect can be undermined significantly by a substantial culet.
The GIA is widely considered to be the most consistent and reliable of diamond labs, offering an extremely rigorous approach to grading diamonds of all shapes for factors pertaining to cut quality â and a great level of assurance to shoppers, even if theyâre brand new to the world of diamonds.
Beyond that, the only other lab we would recommend is the AGS â although even this respected organization comes second to the GIAâs methodologies.
Two diamonds with the same cut grade should not be considered equally if one has been graded by the GIA or AGS, and the other by another lab. You can read our guide to diamond certification here to find out more about this â and which labs to avoid.
Cutting a diamond creates sparkle. After all, even a poorly cut diamond will spark under the right lighting. Only the best-cut diamonds, however, will sparkle in a way that you canât help but stare at and appreciate.
The importance cut quality holds for beautiful diamonds is undisputed â and, while it is one of the Four Cs, itâs not something you should consider to be negotiable (like clarity and color) or down to budget and personal preference, like carat weight.
A good cut is the foundation for any beautiful engagement ring. Focus on finding a diamond with a GIA report mentioning only those top two grades across the board, and youâll be on track for a great investment.
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