Diamond 4Cs Explained

Diamond 4Cs

Diamonds are one of the most expensive stones in the world and their price is usually determined by their size, quality and location. Just about everybody would like to have one in his or her possession. However, purchasing a diamond is a difficult task that can leave a large hole in your pocket. Very few people actually understand how to evaluate and purchase a diamond and most end up spending too much on a low-grade stone.

If you have decided to purchase a diamond engagement ring for your beloved, you will undoubtedly have several things in your mind. This is quite understandable as you are about to make a large purchase and have a wide choice ahead of you. If you are buying a diamond for the first time in your life, you naturally want to get the best deal without losing a lot of money.

Most probably, you will get started by doing a lot of research about buying diamonds, and this is just the right thing to do. Getting the right information about assessing the quality of a diamond is highly advisable if you are serious about purchasing a diamond engagement ring for your beloved.

Before buying a diamond, you must learn everything about the 4Cs of diamond evaluation.

What Are the 4Cs? 

What are the 4Cs

The 4Cs comprise the universal language that defines the unique characteristics of a diamond. The following are the 4Cs and they help buyers to determine the rarity and value of the diamonds they would like to buy:

  • Clarity
  • Color
  • Carat Weight
  • Cut

It was only in the middle of the twentieth century that the Gemological Institute of America (GIA) established a standard of diamond evaluation that got the acceptance of the entire world. Till then, buyers as well as sellers of diamonds had absolutely no common standards of grading diamonds.

The GIA’s standard came to be known as the 4Cs of diamond grading. And it led to the establishment of the GIA as the global authority on diamond assessment and certification. The GIA uses a scale to grade each C and evaluates the diamond for its quality accordingly.

Today, Cut, Clarity, Carat Weight, and Color comprise the universal language that sellers, buyers, and gem testing labs use to communicate the rarity and value of diamonds. The 4Cs tell purchasers all they need to know about the stone they would like to purchase.

To put it in brief, the 4Cs represent the four major components of the structure and beauty of a diamond. When you view a diamond with your naked eyes, you actually perceive the balance of the 4Cs within it. At the same time, you must understand that 4Cs are the not the only factors to be considered while purchasing a diamond. You must also consider shape and certification.

Although the universal language used to assess and grade diamonds is the same, each certifying lab its own methods. But the highly recommended diamond certification labs are the GIA and the American Gemological Society (AGS). We do not recommend purchasing diamonds that do not have either a GIA or an AGS certificate.

The price of the diamond depends on the contents of the certificate that accompanies it. If you understand the system of grading diamonds based on the 4Cs, you will be able to compare and understand the differences between two similar-looking diamonds. At the same time, you must remember that how the diamond appears to your naked eye is most important. A proper understanding of the 4Cs helps you identity the best diamond within your budget.



The way a diamond is cut determines how brilliantly it shines. Diamonds that are cut symmetrically and have facets that are well aligned can reflect light in a beautiful manner and deliver a brilliant effect. An expert diamond cutter can give his diamonds well proportioned facets that can maximize the amount of light they can reflect. The result is a sparkling stone of unrivalled beauty and value.

Diamonds cutters are very careful while cutting their stones as the slightest mistake can reduce their quality and value. For example, a diamond that is cut too flat or given an extra large table cannot reflect an adequate amount of light while diamonds that are cut too deep end up showing dark points in their center.

To put it simply, the cut of a diamond refers to the quality of its proportions, angles, brilliances, facets, fire, and brilliance. Cut is the most important of the 4Cs as impacts the diamond’s ability to sparkle and enhances its aesthetic appeal.

The GIA has assigned the following grades for diamond cut:

  • Ideal
  • Excellent
  • Very Good
  • Good
  • Fair
  • Poor

Diamonds with Ideal or Excellent cuts have the maximum fire, sparkle, and brilliance although a lot depends on the shape in which they are cut too.

The cut of a diamond depends not only on the expertise of the cutter, but also on the nature of the diamond. Sometimes, diamond cutters want to give their stones maximum carat weight, which is why they cut the diamond either too shallow or too deep. Sometimes, their aim may be to minimize flaws and maximize clarity, sacrificing brilliance as a result. Even diamonds bearing the Ideal cut grade may sometimes display yellowish tints that destroy their beauty and reduce their value.

If you want your diamond to be beautiful, you must focus on the cut and not on the carat weight. Even a diamond weighting 2cts will look dull if it does not have an Ideal or Excellent cut grade.



As already mentioned in the opening paragraph, diamonds are natural miracles created within the depths of the earth over a great period of time because of immense pressure and heat. Being created through a time-consuming natural process, they are far from flawless. In fact, most diamonds have blemishes on their surfaces and inclusions in their depths. Diamonds that have very few inclusions and blemishes are said to have higher clarity.

The following terms define the clarity of diamonds:

  • F1– Externally and internally flawless diamonds
  • IF– Internally flawless diamonds
  • VVS1 and VVS2– Diamonds having very very slight inclusions
  • S1– Diamonds having slight inclusions
  • VS2 and VS2– Diamonds having very slight inclusions

Diamonds are graded according to their clarity to evaluate how free they are from blemishes and inclusions. Imperfections can interfere with the passage of light through a diamond, thereby reducing its brilliance and beauty. Such a diamond will not shine brilliantly even if has an ideal or excellent cut.

The diamond you are interested in purchasing should be eye clean. This means that it should appear free of blemishes and inclusions when examined with the naked eye.


1 carat diamond ring color

The GIA has graded diamonds according to their color, as follows:

  • D, E, and F refer to colorless diamonds
  • G and H refer to nearly colorless diamonds
  • I and J refer to diamonds with a very faint color
  • K and M refer to diamonds with a faint color
  • N – R refer to diamonds with a very light color
  • S – Z refer to diamonds with a light color

The cost of diamonds depends on their color grade. When you examine a diamond with your naked eyes, you will not be able to determine the subtle changes in color. If you are looking for stones at lower rates, you should identify the light colored diamonds.

This, however, does not mean that diamonds with color have no value. On the contrary, colored diamonds are valuable just for their color. For example, diamonds colored green, blue, orange, red, yellow or fancy pink are expensive just because of their color. These colored diamonds have a color grading of their own, which is much different from the way colorless diamonds are graded.



Carat refers to the weight of a diamond. For example, you can find diamonds weighing 0.25ct, 0.50ct, 1.00ct, 1.50ct, 2.00ct, and 4.00ct.

In the past, diamonds were weighed using carob seeds. The word carat comes from “carob seeds,” and today, the weight measure for diamonds is carat. Jewelers weigh diamonds up to their hundredth decimal for the purpose of accuracy. One carat is equal to 200 milligrams.

Carat is not to be confused with size. In fact, carat has nothing to do with the size of a diamond. A 1ct diamond weighs 0.2gms or 200mgs. But several 1ct diamonds may have different shapes and sizes depending on the way they are cut.

Of the 4Cs of diamonds, carat is of least importance. Experts advise buyers to consider not the weight, but the cut, clarity, and brilliance of a diamond. For example, a diamond weighing 1.5ct may look larger, but will not have the brilliance, beauty, and elegance of a better cut 1ct diamond with a high clarity grading.

How the 4Cs Make Diamonds Beautiful

How the 4Cs Make Diamonds Beautiful

Each of the Cs has its own contributions to make to the beauty and uniqueness of a diamond. But you cannot consider each C separately while reviewing a stone. The art of diamond assessment becomes complete only when you notice how each of the Cs impacts, interacts with, or complements the others within a particular diamond.

The most important C is the cut as it makes the diamond look beautiful and gives it its value. Check your diamond for high levels of fire and brilliance although you may have to compromise on color and clarity.

The second most important C is the color. When you examine a diamond with naked eyes, it should appear colorless as the slightest color can interfere with the passage and reflection of light within the stone.

Clarity is the third most important C. Select a stone that appears free of blemishes and inclusions at least when examined with the naked eye. Inclusions and blemishes prevent light from entering the stone, thus reducing its fire and brilliance.

As previously mentioned, carat is of least importance. A lighter stone with more clarity and a better cut gives more value for your money than a heavier stone with a poor cut and less clarity. When you shop for a diamond, be willing to sacrifice carat weight if it means getting hold a lighter stone that not only costs less, but appears stunning.

The best tip an expert can give you is to take all the 4Cs into consideration while assessing your stone. Study how each C complements, interacts with, or impacts the other. Check how sacrificing one C for the others can help you get you a better deal. If you are unable to do this by yourself, ask an expert to help you.

As previously mentioned, when you purchase a diamond, you also have to consider two more factors—shape and certification:


Shapes of diamonds

Diamond cut is strongly related to diamond shape, making each diamond unique and giving it a distinct quality. When you visit a jeweler to purchase a diamond, you will have to choose from the following shapes.

  • Round – The most popular shape in the diamond industry is the round brilliant cut. No other shape is researched as much as this one. Diamond cutters have been perfecting this shape for the past 100 years, using mathematical calculations and advanced light theories to make a round diamond as brilliant and as fiery as it can possibly get.

In addition, you can find round cut diamonds in a variety of clarity, color, and cut grades without sacrificing their brilliance.

  • Princess – Most buyers who are choosing diamonds for engagement rings go in for the unique and brilliant princess cut. Its pointy corners and conventional square shape make it one of the most elegant of diamond shapes.

If you are looking for a J grade princess cut diamond, you will have to spend a lot of money. In spite of the price, you may still see a yellowish tint at the corners of your princess diamond.

You will find princess cut diamonds in a variety of rectangular and square shapes.

  • Emerald – If you prefer a lot of your stone to be visible in its gold or platinum setting, you are looking for the emerald cut diamond. It has large rectangular facets and an open large table that highlights its clarity.

You should be a bit careful while buying an emerald cut diamond with a low clarity grade as the low clarity may impact its level of brilliance. Some emerald cut diamonds are cut more rectangular than the others.

  • Asscher Diamond – The Asscher diamond is a square shaped emerald-cut diamond. It bears a strong similarity to the emerald cut diamond except that it is square, not rectangular.

Since a lot of the stone is visible in its setting, you must studying the diamond’s clarity plot on its GIA or AGS certificate to make sure that you are getting a good deal. This is because emerald and Asscher diamonds are cut to highlight the stone’s clarity.

Even if you buy a J grade emerald or Asscher cut diamond, you may still see a bit of color at the corners of the stone.

  • Marquise – When a diamond cutter wants to maximize the carat weight of a diamond, he/she gives it the marquise shape. The result is a bigger stone, the beauty of which is enhanced when set in a piece of delicate jewelry with pear shaped or round cut diamonds. Since a marquise diamond is longer, it can make your fingers look slender and longer.
  • Oval – Oval cut diamonds are just as fiery and brilliant as round cut diamonds. Since they make fingers appear longer and elegant, buyers prefer them for engagement rings.
  • Radiant – The trimmed corners of this diamond make it a great choice for those who love exquisite and delicate jewelry. Radiant cut diamonds look beautiful in combination with round cut diamonds. You will find radiant cut diamonds in various rectangular shapes.
  • Pear – Since pear cut diamonds have a single rounded or pointed end, they are also known as teardrops. Pear diamonds are very popular among those who love unique designs in their jewelry. If you want a ring that will make your fingers look slender and elegant, you can choose a slightly elongated pear cut diamond.
  • Heart – Heart shaped diamonds are for those who are romantic at heart. Diamond engagement rings bearing heart cut diamonds are the ultimate symbols of love, romance, and commitment. A lot of the stone is visible in its gold or platinum setting, so you may see some off white color at its corners. Even heart cut diamonds with a lower color grade are expensive.
  • Cushion – Also referred to as the “pillow cut,” cushion cut diamonds have been very popular for the past century. Their large facets enhance their clarity, which makes them similar to the emerald and Asscher cut diamonds. If you are purchasing a cushion cut diamond, you have to pay special attention to clarity. We suggest checking out the clarity plot, which you will find in the diamond’s GIA certificate.

You will find cushion cut diamonds in a wide range of rectangular and square shapes.


The fact that your diamond comes with a diamond certificate is a guarantee that you are getting a high-quality stone that has undergone an unbiased grading system.

One of the highly reputed gem testing laboratories in the world is the Gemological Institute of America (GIA), which is internationally acclaimed for its unbiased and consistent system of testing and grading diamonds. If you buy a diamond that has a GIA certificate, you can rest assured that you have got a rare and valuable stone.

All well-known and highly reputed jewelers send their diamonds to independent, third-party gem testing labs for thorough evaluation and grading. This is called the diamond certification procedure. Gem testing labs employ well-trained, qualified, and professional gemologists who specialize in testing, evaluating, and grading diamonds.

Accordingly, the gem testing lab thoroughly grades individual diamonds and gives each diamond a certificate bearing a unique number. The certificate, which is transferred to the buyer upon purchase of the diamond, is laminated so that it can never be modified or tampered with.

The diamond certificate presents an impartial review of the characteristic features of the diamond it accompanies. Also known as the diamond dossier or diamond grading report, it gives the purchaser a very good idea of the quality of the diamond he/she has just purchased.

It also assures the buyer that the seller is telling the truth about the grade of the diamond’s cut, color, clarity, and carat. Since the diamond certificate presents an independent and professional valuation of the stone, it can be used when you are insuring your jewelry.

However, you must understand that there is a difference between a diamond appraisal and a diamond certificate. While a diamond appraisal establishes the price of a diamond, a diamond certificate is an impartial and professional statement of its quality and characteristics. A diamond certificate from reputed labs such as GIA or AGS helps in accurately appraising a diamond.

When you are purchasing a diamond for an engagement ring or any other piece of jewelry, make sure that it has a certificate issued by a reputed gem testing lab. We recommend only those diamonds bearing GIA certificates as the GIA is the biggest, most reputed, and oldest gem testing facility in the world.

Moreover, the GIA does not belong to any retailer or wholesaler, which makes it truly independent and unbiased. The credit of developing the 4Cs also goes to the GIA. If you are buying a diamond online, you can click on the GIA link against its image to view its GIA dossier or grading certificate.

Be careful about buying a diamond that does not have a GIA or AGS certificate. Many gem testing labs belong to wholesale or retail jewelers and can, therefore, be biased in their grading procedures.

Moreover, certain unscrupulous retailers control certain labs, force them to lower their standards, and declare low quality stones to be diamonds with high grades. Avoid depending on diamond certificates issued by lesser known labs and trust only reputed ones such as AGS or GIA.

Some of the gem evaluation labs that enjoy excellent reputation are the aforementioned AGS, GIA, and HRD, which is more popular in European countries. If you come across a diamond with certification from EGL and IGI, you will find that it is available at a discount. This is because these gem laboratories employ relaxed grading systems. For example, a diamond that gets a G color grade at EGL may get an H color grade at GIA.

When you shop for diamonds, you will find that diamonds certified in different labs have different prices. This may make you feel that you have found a good deal. In reality, the difference in price is because of relaxed grading systems implemented at different labs. Make sure that you purchase diamonds that have been graded at highly reputed labs. If a retailer offers to do a certification for you, politely refuse it even if the retailer claims to be trained by the GIA.

Store your diamond certificates safely as they come in useful when you lose your diamond or want to sell it. If you are temporarily giving your diamond to a third party, make it absolutely clear that you have a certificate. This will discourage the third party from tampering with your diamond or replacing your stone with a similar-looking stone with low quality. Your diamond certificate can help you to establish the identity of your diamond at any time.

Remember the number of the GIA certificate of your diamond or write it down in a safe place. If you lose your certificate, you can always request the GIA to replace it. The GIA maintains copies of every certificate or report it generates.

The Perfect Diamond

Perfect diamond

Color, cut, carat weight, and clarity all play an important role in enhancing the beauty of a diamond. The 4Cs interact with one another to give diamonds their brilliance, elegance, fieriness, and beauty.

All diamond experts agree that cut plays a greater role than the others in giving diamonds their beauty and elegance. But while focusing on cut, buyers cannot forget to strike a balance between clarity and color to get more value for their money.

If the cut is right, a 0.9ct round brilliant diamond with a color grade of K and a clarity grade of VS2 can look just as stunning as a 1.5ct round brilliant diamond of color grade I and clarity grade S11.

If you need help with evaluating and examining a diamond, you can get in touch with a diamond expert. Alternatively, you can return to this website to read more information about diamond evaluation and get valuable tips on shopping for diamonds.

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