When it comes to selecting a diamond—whether it’s for an engagement ring, wedding band, or just a little something sparkly—there’s a lot that goes into finding the perfect rock. Before making the investment, it’s important to learn the basics of what makes a diamond coveted so that you can select one that’s right for your personal aesthetic and your wallet. Odds are, you’ve heard of the 4Cs of diamond quality. This diamond grading system—which judges the carat, cut, color, and clarity of the diamond—determines a stone’s overall quality. We’re here to break down the 4 Cs for diamonds to help you find the rock of your dreams.
When picking a ring, there are four general components to look for (also known as the 4 Cs of diamond quality): cut, color, clarity, and carat. The term was developed in the early 1940s by GIA (Gemological Institute of America) founder Robert M. Shipley. He developed the institute to provide formal training for jewelers, and it was for his students that he came up with the 4Cs—a mnemonic device to help his students remember the four factors that characterize a diamond. That’s why the 4 Cs apply to both natural and lab-grown diamonds; since they have the same chemical, physical, and optical properties, they can be graded on the same scale.
The concept was revolutionary, because prior to Shipley’s device, there wasn’t a consistent language for jewelers to use to communicate diamond elements to each other and to their customers. Within decades, the 4Cs became integral to the industry’s vernacular, and now evaluating each of the 4Cs when buying a diamond is the best way for a customer to find the ideal rock for their budget, lifestyle, and personality.
Each of the 4 Cs (carat, cut, color, and clarity) play a role in a diamond’s beauty, and they come together to rate the overall diamond quality. As a rule of thumb, having something that’s “pretty good” across the board will land you a gorgeous, quality rock that will (hopefully) not completely break the bank. While you might think that snatching the biggest diamond and forgoing the other Cs is the key, in reality, it’s important to evaluate each component, as they all interact with each other to collectively create the diamond’s overall aesthetic and value.
When it comes to the 4Cs, carat is the only term that was actually common prior to Shipley’s universally used device—and is most likely the one you already know of. The term has been used consistently since the 1500s, but it might not mean what you think it does. Though pop-culture makes it seem like the carat is the size of the diamond, it’s actually in reference to the weight. The carat is the diamond’s physical weight measured in metric carats. One carat equals ⅕ of a gram and is subdivided into 100 points. Still, chances are that the heavier the rock, the bigger it looks to the eye, too.
When considering the carat, keep in mind not only the cost (a decent quality, one-carat engagement ring would come in at about $5,360, on average), but the lifestyle of the wearer, too. Does he/she work with their hands? Will there be risks of potential damage? How will it look on his/her finger? While it might seem like the bigger the carat, the better, that’s not actually the case. According to Diamonds.pro, the average engagement ring diamond in 2020 is between 1.08 and 1.2 carats. Things like the cut, the diamond shape, and the setting (such as a halo, which will make a solitaire diamond appear bigger) all contribute to how large the stone will look once it’s set.
Now, this might come as a surprise to you, but the shape and cut of a diamond are actually different. The shape is well, the shape—the outline or external figure of the diamond. This is where considerations like oval, princess, and pear come up. Most consumers have an idea about what shape they want (and if not, go with round—it’s timeless). But the cut? That’s a different story. The diamond’s cut actually determines how sparkly the diamond is, since it manipulates the way light enters and exits the gem. The diamond’s cut refers to the quality of the diamond’s symmetry, angles, proportions, and finishing details, as well as its brilliance (the white light return, which is the foundation of a diamond's brightness), fire (the colored sparkle), and scintillation (overall sparkle).
Diamond cut is graded by the GIA via a rating scale of: ideal, excellent, very good, good, fair, and poor. For plenty of brilliance, choose a cut grade of at least very good for round diamonds. If you have a fancier shape (such as a heart, for instance), a good or better cut should suffice in the sparkle department (sometimes even a fair cut will get the job done, if you want to splurge on a different “C”). While it might seem unimportant, many jeweler professionals feel that the cut quality is the most crucial component for a gorgeous diamond.
Color is the one “C” that’s pretty straightforward. Basically, diamond color is graded in terms of how white or colorless it is. The GIA grades diamonds from D to Z, with D being the most colorless, and Z being noticeably brown or yellow—and the cost usually reflects these grades, with D being the most expensive. For traditional diamond rings, you basically want something as colorless as possible, so a D-J. That said, the best way to select your diamond color is to first pick the color of a setting. A gold or rose gold setting will offset the yellow in a diamond to give it a more colorless look (which means you can go to lower grades in regard to color) whereas a silver or white gold setting will highlight any color tint in the rock.
Since diamonds in adjacent grades can look pretty similar, be sure to enlist the help of a pro to ensure that you select a rock that compliments the setting. Additionally, if you’re looking for a colored diamond (which is growing increasingly more popular) the color grade is entirely different than for “colorless” diamonds, so you’ll have some additional homework if you’re after a pink, sparkly stone.
All diamonds contain birthmarks. Those small imperfections inside the diamond (inclusions) or on its surface (blemishes) play a big part in how brilliant the stone looks, because significant inclusions and blemishes interfere with the path of light through the diamond. So, a diamond’s clarity is how clear and clean it looks. To determine this, pros use the the GIA Diamond Clarity Grade Scale:
Ranked from flawless to third level inclusions, this clarity grade scale determines the amount and degree of interior and exterior flaws that the diamond has, which negatively impacts its appearance, value, and strength. Since flawless diamonds are so rare (and expensive), they’re usually just purchased by elite jewelers or collectors. Almost all diamonds have at least a small inclusion or two. The most common level purchased for engagement rings is VS2. This will yield a rock with flaws that are usually invisible to the naked eye.
Whatever diamond you choose, just remember, it’s the reason behind the ring that has the real value. It doesn’t matter how big the rock is or how shiny the cut is, because as long as it’s from the person you love, it will be a treasure.