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The 4 C’s of Diamonds: Evaluating Diamond Quality

How to balance the 4 Cs of diamonds to get the best bang for your buck

By Michael Fried,

Each of the 4 C’s of diamonds (Cut, Color, Clarity and Carat) play a role in a diamond’s beauty. The grades a diamond carries in these four areas give a clear idea of the diamond’s quality, and by extension the right price you should be willing to pay.

Here’s what we’ll cover in this article:

What are the 4 C’s of diamonds?
What C of the 4 C’s should I prioritize when buying a diamond ring?
What are the main characteristics of diamonds?
Which of the 4 C’s is the most important?
Bottom Line Recommendations for 4Cs

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What are the 4 C’s of diamonds?

According to Wikipedia Four characteristics known informally as the four Cs are now commonly used as the basic descriptors of diamonds: carat, cut, color, and clarity. This system was developed by Gemological Institute of America in 1953 as internationally recognized standard to evaluate diamonds characteristics.

A diamond’s quality is determined by the 4C’s: 

  • Cut: Quality of the angles, proportions, facets, and finishing details.
  • Color: How colorless the diamond is. 
  • Clarity: How clean the diamond is of inclusions and blemishes.
  • Carat: The weight of the diamond.

These four qualities of a diamond are the key components that impact its beauty and structure. The 4C’s interact with each other within the diamond. They dictate how the diamond appears and how high quality it is. As an example, the diamond’s ability to reflect light back to your eyes depends primarily on cut quality but also on color and clarity. 

The four diamond characteristics are graded by professionals on a consistent scale, giving you a tool to evaluate diamonds. By reviewing the 4C’s of a particular diamond, you can better determine if the diamond is of high-quality. GIA explains why and how diamond grades got created.

The Characteristics of Diamonds

The GIA and the AGS are the prominent institutions with a sophisticated grading system for evaluating diamond characteristics. They are the most consistent entities and the ones we recommend gaining a diamond certificate from. Each of the C’s are graded on a scale, and can be evaluated for quality. Though some universal terminology and standard grading exists, it does vary by lab entity.

Gradings of the 4 C’s help determine the value of a diamond and indicate its quality. Diamond sellers often set their prices based on grading reports. Knowing the basics of these gradings is helpful when comparing two similar diamonds, but what remains most important is how the diamond appears to the naked eye—and how attractive the diamond is overall. In this sense, having a foundational understanding of the 4 C’s is imperative as a buyer, so that you can avoid spending your budget on a component that will go unnoticed.

Diamond Quality

The 4 C’s of diamonds gives you a more objective way to measure and assess the quality of a diamond. Without the 4 C’s, diamond quality is something that is hard to quantify. Any unscrupulous vendor could easily claim a diamond to be high-quality, and thus charge more than it’s worth.

It becomes a lot easier on consumers with a more objective guide on what makes a diamond high or low-quality. Each of the 4 C’s offers a quantifiable description of its quality in certain areas, in turn making it easier to judge whether or not it’s worth its price tag.

Diamond Quality Chart

Diamond Quality Chart
The 4CS of diamond quality

How To Buy An Engagement Ring Using The 4 C’s

There are two major questions you need to answer; Where and what. We have an article covering where to buy your engagement ring. In this article we are covering what characteristics you should focus on when purchasing a diamond.

Without finding the right balance between the 4cs, you will end up overpaying for certain qualities of a diamond while not spending enough on others. Let’s say you are thinking of purchasing a one carat diamond. If you balance the 4Cs you can get a stunning looking diamond like this that is a great value. If you ignore that balance you can end up with a cheap, yet incredibly ugly, diamond like this example from James Allen. Or you can think “only the best” and spend a boatload on this exquisite diamond. But if you follow our recommendations, you can find the perfect balance of quality and value.


The ‘Cut’ is perhaps the most important aspect of a diamond quality that impacts a diamond’s beauty. Diamond Cut specifically refers to the quality of a diamond’s angles, proportions, symmetrical facets, brilliance, fire, scintillation and finishing details. These factors directly impact a diamond’s ability to sparkle, along with its overall aesthetic appeal. For example take a look at this beautiful diamond from JA and this horrific choice. The only issue differentiating the two is their cut.

The GIA diamond cut chart grades Diamond Cut on the scale of Ideal, Excellent, Very Good, Good, Fair and Poor. The Ideal and Excellent grades, depending on Diamond Shape, signify proportions and angles cut for maximum brilliance and fire.

How Light reflects through a diamond
Diamond Cut

Even if two diamonds are given the same grade on the diamond cut chart, cuts vary significantly among diamonds and diamond cutters. At times, a cutter may aim for maximum Carat weight, leaving the diamond too deep or too shallow for optimal light reflection. Other times a diamond may be cut to minimize the number of inclusions, improving its Clarity, but forgoing maximum sparkle. Even an Ideal cut diamond may have a yellow tint that is too noticeable and detracts from the gem’s beauty.

More importantly, though, is ensuring Cut is a focal point of your diamond selection. Even a pristine 2 Carat Diamond with no blemishes or color tinting can be dull if it’s not cut exceptionally well. Cut is the biggest indicator of beauty, and should be made priority over the other C’s. As an example, this 1.50 Carat Round Brilliant is graded well for each “C” but lacks a vivacious sparkle.

It’s essential to note that a top grade designation on the diamond cut chart, such as Excellent, doesn’t necessarily indicate an outstanding diamond cut. Almost 55% of all diamonds sold online are Excellent cuts. Some are stunning, while others are mediocre. An example of an exquisite Excellent cut diamond is this 1.5 Carat Round Brilliant from James Allen.

Also, you might have heard about triple ex diamonds (excellent cut, polish and symmetry). A lot of people think that these diamonds are worth the premium some jewelers are charging but the reality is a bit different. You can read more in our Triple Excellent article that explains it in more depth.

Because Cut is so important to a diamond’s fundamental beauty, it’s crucial to review a diamond’s Cut carefully and ask for the eye of an expert.


Diamond Color is graded in terms of how white or colorless a diamond is. The GIA grades diamonds from D to Z, with D being the most colorless, and Z containing noticeable brown or yellow tint. The diamond color chart below shows how each grade looks next to each other.

While the diamond color chart provides an example of how each grade appears, it’s important to look at each diamond individually. Depending on the diamond’s cut, carat weight and shape, the color might appear different among diamonds.

The pricing of diamonds usually reflects the grade—sometimes significantly. In most cases, the naked eye cannot tell the difference between two adjacent color graded diamonds, though the price difference may be significant.

The most critical aspect with Color is to determine if it appears colorless in relation to its setting. You also want to be certain that a diamond is clear of any tinting that takes away or interferes with white and colored light reflections. The K Color in this Cushion Cut Diamond from James Allen, for example, distracts from the sparkle of the diamond while this H Color Diamond from James Allen is radiant.

Brilliance, or sparkle, is created from the way the diamond is cut. It is not advantageous to purchase a diamond that distracts from this important principal characteristic.

As a general recommendation, review each diamond closely and ask for the assistance of an expert. This is the best way to ensure you’re not paying for a feature (i.e. too high of Color grade) that will go unnoticed, or purchasing a diamond that distracts or interferes with light reflection.

Note: Certain colored diamonds are valued stones, like a fancy pink or green diamond. Color grades for these diamonds are distinctly different from traditional “white” diamonds and don’t appear on the diamond color chart.

Diamond Color Chart

Diamond Color Chart
Diamond color chart


A Diamond’s Clarity grade evaluates how clean a diamond is from both inclusions and blemishes. Clarity is graded by the GIA on the following diamond clarity chart:

  • FL (Flawless)
  • IF (Internally Flawless)
  • VVS1 (Very, Very Slightly Included 1)
  • VVS2 (Very, Very Slightly Included 2)
  • VS1 (Very Slightly Included 1)
  • VS2 (Very Slightly Included 2)
  • SI1 (Slightly Included 1)
  • SI2 (Slightly Included 2)
  • I1 (Inclusions 1)
  • I2 (Inclusions 2)

Note that each diamond differs slightly. Rather than sticking to a particular grade on the diamond clarity chart, review each diamond to see if you notice imperfections.

Diamond Clarity Chart

This diamond clarity grading scale shows and sums up each clarity grade. Watch how the visibility of the inclusions changes in the image on the right.

As you work your way across the diamond clarity chart, you’ll notice how more inclusions and blemishes are visible. Not all imperfections are visible to the naked eye, though. That’s why it’s important to look at each individual diamond.

Diamond Clarity Chart
Diamond clarity chart

Depending on the size, location and darkness of blemishes and inclusions, these imperfections can interfere with light as it passes through the diamond. When this happens, the brilliance and beauty of the diamond is dulled, taking away from the high-quality Cut.

For Clarity, our primary recommendation is to ensure the diamond is eye clean, and that inclusions are not interfering with light reflection.

Review the stone to see if it is eye clean and ask for confirmation from an expert. A certificate alone won’t tell you how a diamond’s blemishes will impact the stone’s appearance and brilliance.

Eye-Cleanliness is Paramount

In our opinion, a consumer’s goal should be to find the cheapest (in regards to clarity; other factors matter as well) “eye-clean” diamond you can find. We use “eye-clean” to describe diamonds that may have inclusions if you look at them with a magnifying glass (or microscope or loupe), but the typical person can’t see the inclusion with their naked eye.

We have recently developed Ringo, a patented artificial intelligence model, that can examine videos of diamonds and determine if they are eye-clean. Ringo will also filter for other parameters like making sure the diamond is well-cut, doesn’t have fluorescence issues and will match the style setting you choose.

Ringo Approved Eye Clean Diamonds

What is Ringo?

Carat Weight

Often when people hear the term “Carat Weight,” they think it refers to the size of the diamond. In actuality, Carat refers to the weight of the diamond, not how large the stone is. A 1 Carat Diamond equals 200 milligrams, or 0.2 grams—and weighs about the same as a quarter of a raisin. Depending on the Diamond Shape and how it is cut, two 1 Carat Diamonds might be quite different in size.

Round cut diamond carat weight size
Carat weight vs size

While Carat weight is an element to consider when buying a diamond, the overall appearance and brilliance should carry more importance. For example, a mediocre 1.5 Carat diamond will not shine as brightly—or draw as much attention—as a stunning 1.0 Carat diamond, no matter how much more it weighs. Rather than sticking to a certain number on the diamond carat weight chart, choose a diamond with an Excellent cut or Ideal cut in the shape you desire.

How the 4 C’s work together

Each of the 4 C’s contribute to the overall beauty of a diamond and make each stone unique. A Diamond, however, should be viewed as an organic whole. Because the eye has difficulty differentiating one diamond characteristic by itself, such as Clarity or Color, it is important to consider how the 4 C’s impact each other.

Which is the most important of the four C’s?

  • Cut: The most important of all the diamond characteristics as it most readily impacts a diamond’s beauty. Look for high levels of brilliance and fire, and be willing to reduce your spending in other areas like Clarity or Color to ensure an exceptional Cut.
  • Color: The second most important aspect to focus on. A diamond should look white or colorless to the naked eye. Ensure the Color does not distract or interfere with white and colored light reflection.
  • Clarity: The third most important characteristic on the list. Choose a diamond that is eye clean. Blemishes and inclusions should not distract from the brilliance or fire of a diamond.
  • Carat: Last but not least. Based on how you balanced out the other 3 C’s that will determine how large of a diamond you will end up with. If you balance everything perfectly, you will get the largest possible diamond in your budget that looks fantastic.

With these fundamentals in mind, remember that a diamond is a precious whole, and should be looked at in totality. The four main qualities of a diamond all play an important role in how the diamond looks.

Bottom Line Recommendation:

As a general rule, we suggest a high quality Cut above all else—as this greatly impacts a diamond’s beauty and brilliance—while balancing a fine line on Color and Clarity to get the best bang for your buck. With the right cut, even a J color like this can be a winner.

Knowing what to look for and how to balance the 4 C’s will help you get the best value for the perfect diamond for you.

What to Look For
What to Avoid
Prioritize Cut over all of the other 4 C’s. For a Round diamond, make sure it has an Excellent or Ideal grade in Cut.
Don’t overpay on color and clarity. A higher grade may result in a premium price and no visible difference.
Find a balance between each of the 4 C’s, so each quality works together to elevate the beauty of the diamond.
Avoid putting too much of your budget towards carat size while sacrificing too much in other areas.
Look for diamonds graded by the GIA or AGS, over any other labs, to ensure its grades are fair and accurate.
Don’t buy a diamond off its grades alone. Inspect the diamond yourself to ensure it lives up to its certificate.
Having trouble navigating the diamond buying minefield? We are happy to help. CONTACT US

Need More Help on The 4 C’s?

Even with a basic understanding of the 4 C’s as a guide, navigating the diamond industry can be difficult. From picking which of the 4 C’s to prioritize, to assessing whether a diamond actually lives up to the grades it’s been given, there’s a lot to take in.

The recommendations related to Cut, Color, Clarity and Carat weight in this guide should give you a good starting point for your search. It also helps if you shop with a reputable vendor, as this dramatically lowers the chance that you’re going to get ripped off. For the best place to buy an engagement ring, we recommend James Allen, both of whom offer top-quality customer service, and an excellent range of diamonds at amazing value.

We’re here to help with anything you need in your search for the perfect diamond. If you’re unsure how to evaluate a diamond, and want to purchase an exceptional diamond that’s within your budget,
contact one of our experts
for assistance.

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About the author

Michael Fried Michael Fried Mike Fried has over 25 years experience in the diamond industry working with Leo Schachter Diamonds, Moshe Namdar Diamonds, and joining The Diamond Pro in 2007. He is recognized as an industry expert and has been quoted in publications such as Us, People, Page Six, The Next Web and more.

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