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Ways to Identify The Quality of a Diamond

Diamonds naturally come in a wide variety of colors, sizes, and shapes. However, all of them contain some intricate combinations of different characteristics that make them unique, and these characteristics help determine the value of a diamond. It is, therefore, important to know the kind of characteristics you should keep in mind when looking for the best diamond. A great place to start is by learning about the 4Cs of diamond quality.

The 4Cs of Diamond Quality

According to the American Gem Society (AGS), shoppers should be looking for an assurance that the quality they pay for when buying a diamond is the quality they are getting. After all, diamonds are expensive. Expert appraisers and jewelers have the skill, knowledge and experience needed to evaluate the quality of a diamond. Expert graders and jewelers can assess your diamond using a systematic system for specific characteristics.

Still, knowing as much as possible about diamonds before making a purchase is a valuable thing to consumers. Fortunately, you can learn and use the same grading system that the expert graders and jewelers use.

The grading system assesses the 4Cs – when these characteristics are combined, they can paint a really good picture about the quality of the diamond. The 4Cs of diamond quality are:

  • Clarity
  • Color
  • Carat Weight
  • Cut

All these characteristics are important when determining the quality of a diamond and all are considered. Additionally, the official certification a diamond is given is just as important.

The following are 5 key ways to evaluate the quality of a diamond as experts do.

Carat Weight

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Carat weight is definitely the most objective characteristic of the 4Cs. A digital scale is used to measure the carat weight of a diamond. Larger diamonds are usually worth a lot more than the smaller ones, and in most cases, the value and quality of a diamond has to do with its carat weight.

You might be familiar with the fractional carat delineations of diamonds, such as one, one-half, or one-quarter. However, carat weight is best represented by decimals and usually referred to as DTW, which is diamond total weight. A diamond could be marked at one carat in the store, while it actually has a carat weight of 0.89, or .89dtw. This is a rounding practice often used in retail stores to help make the value of the stone seem higher. Nonetheless, all other factors being equal, a diamond with a carat weight of 0.89 carats should be less expensive compared to an actual one carat piece.

It’s important to know that not all carat weights are equal. Carat weight is simply one of the factors that go into determining the value of a diamond. As such, a two-carat piece of lesser cut, color and clarity should be less expensive compared to a one-carat piece of higher quality. In other words, this method of measuring quality could give you a skewed perception of value. To compare diamonds by carat weight is like comparing paintings by size. 

Keep in mind that a diamond might look bigger than another even when they both have the same carat weight. This is because some diamond shapes will tend to look larger than others. For instance, an emerald cut one-carat round diamond might appear bigger than a cushion cut one-carat diamond, even when they both have the same weight. It’s not your eyes playing a trick on you; rather, it’s solely because of the diamond’s shape.

As such, it’s best to always account for all the 4Cs, not just the carat weight when assessing the quality of a diamond.

Color Quality

The color of the stone will have a huge impact on its value. Generally speaking, the perfect diamond is colorless. Any hint of color on a piece will cause a dramatic difference in its quality. And as you move down the color scale, tinges of brown or yellow appear on the stones, and this lowers the quality and the value of the diamond.

Most of the differences in color are so minute that they are practically invisible to the inexpert eye. Nonetheless, these distinctions usually make a dramatic difference in the price and quality of the diamond.

It’s important to note that there is one exception to this rule. Having color doesn’t necessarily lower the value of a diamond, especially when the color is judged to be a special color, such as “canary yellow” or a “red diamond” which is the ultimate in rarity. These colors actually make the diamond significantly more expensive.

The color quality of a diamond is evaluated using a 23-color grading scale that ranges from D to Z. Every letter corresponds with the 5 subcategories of quality.

As mentioned previously, the more colorless a diamond is, the higher its value and quality. However, color is a subjective characteristic in the 4Cs. The environment in which the diamond is being evaluated can have a considerable effect on its appearance. The metal and the setting are also known to affect the appearance of the stone. Women are also statistically much more sensitive to differences in color, even in diamonds, than men.

All in all, the color quality of the diamond matters a lot. A 4-carat stone with an “S” color grade can be significantly less stunning compared to a 1-carat colorless diamond. If you’re looking to judge the color of a piece yourself, it’s wise to borrow a few tips from the experts.

Turn the stone with the face pointing down and place it on a white background, say a sheet of paper, ideally in a well-lit area. This should enhance any tint of color present and you can then decide what range you’re comfortable with before making the purchase. Just don’t forget that while color is often graded from the bottom, the pieces themselves are viewed from the top, and you should consider the look of the entire diamond before you rule out a color grade.

Clarity Rating

Another key element to understand is the clarity element of your stone. A flawless piece doesn’t have any surface imperfections or inclusions, while a poor quality piece will have inclusions that can be seen by an untrained eye and might even have chips or other kinds of surface aberrations.

You might be wondering how clarity really affects the value and quality of a diamond. Well, as AGS points out, clarity is important when evaluating the value of a diamond because of the idea that diamonds with a high clarity are rarer. As such, clarity is not only an important characteristic in the rarity of a stone, but a diamond with a low clarity grade may be actually less brilliant and may even have a cloudy appearance. Poor clarity grade diamonds are also prone to cracking, chipping, or even shattering, especially if the inclusions are at the edges of the diamond.

The clarity characteristics of a diamond are graded by examining the piece under 10x magnification. The clarity rating is then indicated using a scale with 11 clarity grades, which are quite important to understand.

To get a more detailed look at a stone, you can always see if you can get a jeweler’s loupe to examine the stone under magnification. However, it can be quite difficult for a layperson to judge for clarity. You want to be sure that you check the diamond outside of the bright fancy lighting in a jewelry store, as the lights are designed to enhance the brilliance of these stones and help hide the visible clarity characteristics. 

Cut Quality

The quality of the cut is of great aesthetic importance. A well-cut diamond is designed to dazzle, as every facet and angle of the piece interacts with the surrounding light. Round diamonds generally have a fairly objective cut quality. For the fancy shape diamonds, and any other shapes other than round, judging the cut quality is a bit more subjective.

A well-cut diamond will also have more sparkle and life than one with a lesser cut quality. A good cut will generally encompass three optical effects to make the stone stunning:

  • Brightness: This refers to the reflection of white light in the diamond
  • Fire: These are the flashes of color exhibited by the diamond as it refracts light due to the prismatic effect
  • Scintillation: This refers to the play between the light and dark areas of the diamond

AGS and other diamond graders use a 10-point scale to gauge the cut quality. However, different grading labs use slightly different nomenclature. Therefore, knowing how the cut quality of your diamond is evaluated is critical when it comes to understanding the quality of your diamond.

AGS grading for cut quality ranges from:

0 – Ideal Cut

1 – Excellent cut

2 – Very Good Cut

3 to 4 – Good Cut

5 to 7 – Fair Cut

8 to 10 – Poor Cut

Many people often confuse the cut of a diamond with its unique shape. Although the cut is related to the shape of the stone, the shape and the cut are not the same. Most people are familiar with the brilliant, round cut diamond, but many are less familiar with the fancy shapes. Some of the more popular fancy shapes include the pear, princess, emerald, cushion, marquise, and oval. Some of the lesser-known shapes are heart, asscher, and radiant.

To judge the cut quality of a diamond, you want to avoid using tools such as the Holloway Cut Advisor, which is horribly inaccurate and outdated. You want to view the piece in person. There’s no better way to judge the light performance of a piece than seeing it for yourself in person. You will instantly know whether you are happy with the performance or not.

Try examining the stone under different types of lighting, including natural light and indoors, to get the best feel. Move the piece around to notice how it sparkles whenever light hits it. Just keep in mind that if there’s poor lighting, you shouldn’t expect a lot of brilliance from the diamond – they don’t generate light on their own!

Diamond Certification

The 4Cs are the gold standard when it comes to checking the quality and value of a diamond. As such, it’s important to familiarize yourself with them, so that you can tell where each diamond you come across lands on the 4C grades before making a purchase. You shouldn’t just take a jeweler’s word for it. Be sure to verify the diamond’s quality by looking at its official certification.

This certification refers to the documentation of a diamond’s quality by a third party. It’s not a certification by the seller or buyer. Diamond certifications have become increasingly important due to the prevalence of diamond scams. 

Diamond certifications include detailed information about the diamond’s carat weight, clarity, color, and cut. For instance, the report will come with computer-generated images of the diamond with marks to indicate the location of every inclusion. The image will usually also provide information about the various proportions of the diamond. Along with this image, the report comes with a table that shows where the diamond falls in terms of the cut, color, and clarity grading.

To ensure that they are original, diamond certificates feature inbuilt security features. They are issued by some of the most reputable diamond graders in the U.S. and Europe. Making sure that a diamond is certified by one of these reputable diamond graders is of absolute importance when assessing the quality. Consider also using a diamond “Report Check” online, provided by GIA. To check your report for authenticity, just enter the number at the top of the certification to verify it.

There are so many elements that support a diamond’s true brilliance. You can never be too informed when buying a diamond. To learn more about this subject, be sure to check out Brilliance.com, specifically the diamond quality education section.