What is a Diamond’s Cut?

What is a Diamond’s Cut?

Posted by Koorosh Daneshgar on Feb 15th 2020

Grade, quality, and price of diamonds 

What is diamond cut

A Diamond’s cut is one of the most important features for diamond pricing and its sparkle. Before purchasing a diamond engagement ring, you should first read this article to learn more about the different aspects of a diamond cut.

What is Diamond Cut?

The diamond cut is a delicate work of art, by creating the mathematical proportions and the symmetry of the diamond structure, the diamond brilliance and sparkle is strengthened adding to light reflection. Diamond cut grade has an important effect on its value.

Diamond cut grade Percentage of depth Percentage of table
Excellent 59% - 61.9% 53% - 58%
Very good 58.1% - 61.3% 52.5% - 63%
Good 56.1% - 64.3% 52.5%- 65%
fair 64.5% - 70% 62% - 64%
Poor More than 70% More than 66% - less than 53%

There are many things to consider in the world of diamond cut recognition. But don't worry. in this article we will educate you on some details about methods of the diamond cut, diamond cut grade, and how diamond-cuts impact the price and sparkle of the diamond. All, so you can learn and understand how to select the best diamond ring.

Why is diamond cut important?

Excellent diamond selection is about excellent cut selection because the diamond cut directly effects the beauty and price of the diamond.

It may sound exotic to you, but you need to know that the value of a good diamond ring is not just about its carat weight, but it is also about diamond brilliance and diamond sparkle. You should know that the excellent diamond cutting is one of the most important parameters that make a diamond sparkle. But how?

Diamond cutting is a very delicate work of art that is evaluated according to a standard framework, called ‘Diamond Cut Grade’. If the diamond is cut properly and professionally, the glory and sparkle of the diamond will be multiplied, and vice versa, if the diamond with high quality is not cut well, the value will be greatly reduced.

When you want to buy a diamond engagement ring it is important to make sure that you do not pay more than the actual value of the diamond. It is important to make sure that you do not waste your budget, and you can only gain this guarantee by increasing your information. Part of this information comes from personal study and experience; the other part of this information comes from the help of trusted and knowledgeable experts.

In this article, I will try to play a small role in enhancing your information, especially about the diamond cut.

The difference between diamonds cut and diamond shapes

A common misconception among diamond wedding rings, occurs when we talk about diamond cuts, people often assume that the diamond cut is the same as the diamond shape and instantly think of heart, pear, princess, round and oval shapes of diamonds; and they’ll say: "yes we know all kinds of diamond cuts."

However, when we talk about the diamond’s cut, we do not mean diamond shape at all. In fact, diamond’s cut is about the multidimensional and symmetrical facet of the diamond that can reflect the light that is applied to each of these facets from the top. As you can see any diamond shape also has a diamond cut.

Diamond Cut Vs Diamond Shape

How do they cut diamonds?

Diamond cutting is a delicate, hand-crafted art that needs a lot of experience and accuracy. As you may have noticed by now, diamonds, like any other stone, do not necessarily have a smooth, brilliance and beautiful structure from the beginning and must undergo subtle processes to show its shine and beauty. This process is called diamond cutting.

To start this process, the diamond experts analyze the sample size of diamonds with the help of advanced computer software available today. Diamond experts will analyze the results of computer analysis to decide how to choose the shape and size of their diamond, and at what point can cut the stone to have a better diamond shape from that stone.

Through this analysis, the cutters will decide which part of the stone should be cut as the table (the top flat largest facet), and which aspect should be cut as the girdle (the outside edge) of the diamond.

After that, they start cutting the stone by special tools. For example, they keep the symmetry of the cuts with some marks. They need special tools for polishing the diamond. Yes, you guessed right! It can take 3 to 4 weeks to cut a diamond. 

Diamond Cutting Method

There are four special and general steps to cut a diamond:

The first step is cleaving. In the first step, it is necessary to convert large and irregular stones into small and controllable stones. At this point, the stone is held in a wax-like mold so that it can be cut into smaller pieces using blades of steel. Diamond cutters make a groove on the stone and then with the pressure of strikes of the steel blade into the groove can cut it.

The second step is to saw the stone. If it is not possible to cleave the diamond because of the stone’s hardness, then the diamond cutters will cut the diamond by using another technique which is sawing. In this stage, they can cut the diamond stone by using the laser or a special blade that rotating 15000 times per minute.

The Third step is cutting that is our main topic. After cleaving or sawing the stone then we have a piece of diamond in a suitable size. At this point, diamond cutters can shape the stone with delicate cuts. Obviously, the ultimate purpose of the cut is that while creating a beautiful stone, these cuts should make symmetrical facets that are able to reflect light from the top surface of the stone to give the diamond a unique look.

It is interesting to know that diamonds are usually used to cut other diamonds. This is because diamonds are the hardest stone and other things cannot cut it easily.

Although cutting is the most difficult and sensitive part of this process, but it is not the end.

The fourth and final step of preparation of the diamond is called polishing. At this point, the cut diamonds are polished using a special polishing wheel, which is covered by a sanding-like plate for polishing the diamonds. This way, the surfaces of the diamond are abraded smooth and then the diamond can show its highest degree of reflection and sparkle.

Have a Custom Creation and get your favorite diamond cut

The Heart and arrows pattern

The appearance of the orderly pattern of the heart and arrow, which, can be seen with the help of special tools, with a red or blue filter, indicates the ideal cut diamond. The more symmetrical the pattern is, the more likely you are to have a sparkly diamond.

The shallow diamond cut

When the diamond cut is too shallow, the incoming light will move through the diamond and escapes the diamond from the lower facets. In this case, the diamond cannot provide any brilliance or sparkle.

Sometimes the size of diamonds with shallow cuts seem bigger, but in fact, their glory and beauty are significantly lower than diamonds with an ideal cut.

Deep diamond cut

When the diamond cut is too deep, the incoming light will be directed to the bottom of the diamond and paled light will leave the crystal from the bottom facet of the diamond. This kind of reflection will reduce the brightness of the diamond.

Other negative features of deep cuts include that the size of deep cut diamonds seems to be smaller than the same size diamonds with Ideal cut.

The Ideal diamond cut

The ideal cut is neither shallow nor deep. In this case, the light that is reflected in the diamond surface will return to the diamond’s top facet instead of reflecting from the bottom and side facets. The ideal diamond cut with its unique brilliance, can actually transform a diamond from a simple stone into a precious jewel.

When the diamond cut is ideally, it maximizes the light that will reflect from the top of the diamond. In this kind of cutting, there is no light that escapes from other facets and all incoming light will be centralized in the table facet. For this reason, diamonds with ‘Ideal’ cut are more luminous.

Which diamond cut is most sparkle?

If the diamond is cut ideally, the light rays will move from each face of the diamond to another faced and eventually reflect from the top of the diamond and you can see the unique sparkle of the diamond.

Although the overall symmetry of the round shape diamond enhances the sparkle, we must not forget that even a round shape diamond without an ideal cut cannot display this property perfectly. The ideal cut should neither be deep nor shallow.

You can read more articles about choosing a sparkly diamond in this blog: How To Choose a Sparkly Diamond?

How to choose a sparkly diamond?

What are diamond cut grades?

As GIA suggested there are 5 levels to show diamond cut grade.

1. Excellent
2. Very good
3. Good
4. Fair

As you can see in the diamond cut grade chart the excellent cut grade diamonds have the highest sparkle and the poor cut grade diamond have the lowest ability to provide brilliance.

The Ideal diamond cut grade

The ideal diamond cut grade is an excellent grade. You may think that a very good grade can be an ideal diamond too, but the truth is that today, by the many improvements in this field, diamonds lower than excellent grades are no longer considered to be ideal.

In fact, when you want to select an engagement ring, choosing a diamond ring is one of the best choices. When you decided to have the best choice between all kinds of engagement rings and you are planning to spend your budget to buy a diamond ring, which is the most fashionable and special one, you have to choose the best of the best between all of the available diamonds too.

Yes, you guessed right, the best GIA diamond is an excellent grade not only the very good one. Why, you may ask?

The answer is obvious. Because by choosing the wrong one, all your efforts and planning on buying a wedding ring or engagement ring will be lost. If you are going to buy a diamond that does not reflect the light ideally…why buy a diamond at all?

Excellent diamond-cut causes the masterpiece light reflection and providing the diamond brilliance. Those features making this stone as an Ideas jewel. So in our choice, we should never lower our expectations of this extraordinary stone from excellent cut grade to just a very good one.

The effective factors for cut grading

Qualified Diamond graders should check different properties for grading diamonds. Some of those features include:

Diamond cuttable (table is the top largest central facet of the diamond and most of the diamond shine should be reflected from this area)

Angles (pavilion and crown)

Length (star, lower half)

Crown height

Girdle thickness

Depth (total, pavilion)

Polish (the shine and luster of the diamond)

Symmetry of cuts

Expert diamond graders evaluate each of these features based on their own experience and knowledge to select the diamond's grade. This grading knowledge is according to professional standards too. In fact, there are standard percentages for each angle and facet in any shape of the diamond.

For example, a qualified diamond grader knows that the percentage of a table facet in an excellent cut grade is a number close to 57 percent.

Another example is that in a round shape diamond, experience shows that the depth percentage of an excellent cut should be in the range of about 59 to 62 percent. Likewise, each component of the diamond cut is carefully examined and finally, they can select an excellent grade by rating all grades.

How to make sure of the diamond cut grade?

You should find authentic jewelers and ask for diamond certification. Of course, recognizing the cut grade is very complex and needs qualified diamond grader. Authentic jewelers with many years of experience can help you to have a better choice. They will provide you a diamond certificate which will ensure that the diamond you buy has excellent quality.

Diamond Cut Grades

Why is the diamond certification important in cut grade?

As you have seen, the degree of diamond cutting should be determined by diamond specialists. But those expert people with the help of authentic jewelry stores have made it easy for us by providing special certification for each diamond. In fact, being able to trust a diamond cut grade because of the credibility of a reputable jeweler is a good option that can make your shopping enjoyable and easier.

So, to be at ease of mind, it is better to go to the reputable jewelry stores that can provide you the certification of the diamond.

Does diamond certification only include the cut grade?

No, these certificates are not just about degree of cut grade but also authentic jewelry stores provide you any information that is important about diamonds such as certificate date, logo, color, clarity, cut grade, carat weight, precision measurement (width, length, height), diamond shape, laser bar code Inscription and any information that guarantees the health and quality of the product. Having such certification will identify your diamond and you can rest assured that you have purchased an ideal diamond.

If you have never heard about those certifications or would like to know more, you can check out the link below. What is an Independent Diamond Certificate?

What can we do for the not excellent cut?

Diamonds that are not cut well cannot shine and provide brilliance. On the other hand, some old cuts also have a low luminosity problem compared to modern cuts that made with up to date technology and facilities. In this case, sometimes it can be compensated by cutting the surface bugs again.

This is not always possible and sometimes it is not profitable to recut the loose diamond. sometimes recut the diamond cost more than the true value of it, so to keep your cost down you need to consult a qualified diamond specialist to determine that is the recut the diamond reasonable or not.

Does Diamond Cut affect the price?

Yes! Diamond cutting is one of the most important features for diamond experts to pricing this unique stone. If you also surprised by the glory and brilliance of a diamond and say to yourself, “I don't know why I think this diamond is so much more attractive than the other diamonds?”, pay attention to the diamond cut to find your answer.

Diamond cutting, which is one of the quadripartite parameters (4Cs) suggested by the Gemological Institute of America's (GIA) to evaluating the diamond value, can at least visually affect the other parameters.

In other words, excellent or ideal cuts can make the diamond look more sparkle even compare with heavier carat weight. Contrary to the public perception, what enhances a diamond's value is not only its carat weight, because if the diamond is cut properly and beautifully, then it looks larger and more magnificent than another diamond with the same carat weight. Keep in mind that a good cut can multiply the diamond's sparkle and diamond with more sparkle seems bigger than its true weight.

Thus, it is not surprising to see when you want to buy a diamond ring, what you end up spending the most on is on the diamond cut. Because in the first phase, you like that diamond and its excellent cut- then other features like carat weight, color, and clarity are taken into consideration. In fact, at first glance, this is the excellent diamond cut that makes the diamond look brighter and bigger.

What is the most expensive diamond cut?

The higher diamond cut grade in the most expensive diamond. Excellent grade in the best one and the most expensive one because the Professional cutting doubles the beauty and the glory of the diamond.


What is the cheapest diamond cut?

It is clear that any diamond cut with low cut grade will reduce the value and price of the diamond. For example, if the diamond facets are not symmetrical, different sides are not aligned, deep or shallow cuts which all have a bad effect on the diamond sparkle and its glory and shine will make the diamond cheaper.

So, the cheapest diamond cut is the poor cut diamond grade which cannot reflect the incoming light from the table facet and most of the light will escape from the underside instead of the top facet of the diamond.

Is the price related to the country?

In addition to the cutting structure that affects the price of this precious stone, it should be noted that another pricing factor about cutting is to know where or in which country the diamond is cut. You may be interested to know that some countries are known for their long experience in diamond cutting with high quality. Despite such fame and quality so diamonds produced in those countries are also more expensive too.

For example, countries such as Belgium, Russia, Israel, India, and South Africa are known for cutting diamonds, while Russian and Belgian diamonds have become world-renowned between gemologists. So it is clear that the price of diamonds from those countries is higher.

But it is also important to note that expensive diamonds or only the name of Russian diamonds do not necessarily represent a better product. You need the advice of a diamond expert to identify quality and approved diamonds.

Cheap diamond or ordinary ring?!

The glory of a diamond is because it can reflect the light, and it owes this ability to its cut. Of course, the main difference between diamonds and other stones or crystals is their ability to reflect the light that has made this crystal expensive and renowned.

The first and main criterion in selecting the wedding ring is your style and desire which come from the heart of your love and your romantic relationship.

But after that, In my opinion, if you have a limited budget and want to buy a diamond that does not have any shine, it is better to spend this money on buying a simple wedding ring because as I mentioned, the glory of the diamond ring is because of its shine, and diamond without sparkles has no different from ordinary stones.

What are 4Cs

What are the 4 C’s?

The Gemological Institute of America (GIA) suggested the ‘4Cs’ pattern to evaluate the diamonds. These 4Cs are: 1- color 2- clarity, (if you are interested you can read more about colors and clarity here What Is The Color And The Clarity Of The Diamond? 3- carat weight and Number four, our main topic is evaluating the diamond based on its 4- cut.

What is the position of the diamond cut in the 4Cs pattern?

The cut grade is the most important parameter of this quaternary pattern because it has a large effect on the clarity of the diamond and also we can see that on the contrary to what the carat weight of a diamond indicates, the diamond with optimum and excellent cut grade seems bigger and more sparkle.

Another reason which makes diamond-cut more important than other 4Cs is that recognizing the cut grade is not simple and needs many years of experience.

Although studying an article may not be equivalent to many years of experience, but in this article, I have tried to explain this specialized topic to you as simply as possible. After reading this article and by consulting with an informed and skillful person you can be sure that you will spend your budget on buying the diamond ring optimally and in the best way.

Are Bigger Diamonds Better?

Never forget that looking greater doesn't necessarily represent more value for diamonds. For example, it seems that shallow cut makes the diamond look bigger but at the same time diminishes its luminosity, clarity, and beauty.

Once again you noticed how much the diamond cut is important and sensitive.

How to Choose the Perfect Diamond?

Excellent diamond selection is an excellent cut selection. Don't worry if you have a limited budget, by the advice of a skilled jeweler you can choose a high-quality diamond with perfect cuts that exhibit the same sparkle and dreamy beauty which you can see in bigger diamonds. Even with a limited budget, you can gift the eternal light performance to your beloved by choosing the perfect diamond cut.

As you’ve read, diamond cuts have a lot of details to them. If you would like to know more about it, here is the link in which you can read more about the best diamond cut. What Is The Best Diamond Cut?

Why should I come to you to design my ring?

We involve you in every step of the process. At first, we will sit next to you and go over any concerns you have and any specific design elements you mind the ring to have. Once we have established exactly how you want the ring looks like, we will proceed with the design process. Once you see this design, if you want to make any change or if you have any questions or concerns we will be happy to address them for you. Our role is to help you to create the perfect ring and that means we will listen to you and make sure that your ring is indeed one of a kind.

We'll help you to design your dream engagement ring without stress and spending countless hours searching for your perfect ring. All you need to do is click on "Free Consultation" to get started.

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By: Koorosh Daneshgar CEO/Design Chief

Email: Koorosh@WeddingBandscompany.com