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The Four Cs Of Loose Diamonds [Quick Explanation]

The Four C's Of Loose Diamonds [Quick Explanation]

I'm sure you've heard it before - the famous "Four Cs" of diamonds. You've probably heard that you need to know them in order to buy the best diamond out there. But what are those Four Cs and what do you actually need to know? We're here to help!

Understanding the Four Cs of diamonds is an essential part to buying any loose diamond, yet few people actually understand what they actually are. Each of the Cs plays a major role in the ultimate value of any loose stone. It's crucial to know why some stones are more valuable, and pricier, than others. 

It's time to learn vocabulary that we use on a daily basis when it comes to negotiating diamonds.


A well-cut diamond acts as a prism, splitting white light into a brilliant rainbow of colors. If a diamond is cut well, the angles are positioned just right so that light enters and leaves the diamond in the most brilliant way. If you want the most sparkly diamond out there, make sure your diamond is cut well. To us, it's one of the most important factors when considering any loose stone. Avoid stones that are cut too deep or too shallow because they maximize size rather than light performance.

Diamond Cut


Color is actually a measure of how much color (e.g., yellow, brown, etc) is present in the diamond. More desirable stones are colorless, aka void of any color; they're also more rare and therefore more valuable (and pricey). You want to aim to purchase a diamond that is almost perfectly clear or at least to the naked eye. At Long’s, our standards of color are very high and we typically carry diamonds within the D – J range on the GIA color grading scale (see below):



The difference between each color grading is very slight to the unaided eye, and a well-cut diamond can appear to have less color than it actually does.


The clarity of a diamond describes the inherent imperfections or flaws of the stone. These different flaws can be things such as dark spots, feathery cracks, or white points in the loose diamond. While flawless diamonds are the rarest, a diamond does not have to be flawless in order to be stunning. A lot of times these flaws are almost impossible to see with the naked eye. (Click here to read all about eye-clean diamonds). 

Here is the GIA's clarity scale for evaluating diamonds:



Carat is the measure of a diamond’s weight, not size. Two 1-carat diamonds can look very different based on the cut of the stones. Diamond cutters are given the opportunity to cut a diamond as big as they can to maximize weight or as beautiful as they can to maximize performance. The trick is to find the right balance of carat weight and cut that works for you. Did you know that a 1ct and a 3ct diamond can look exactly the same from the top as well?

Just beginning your diamond search? Make sure to check out the Long's Diamond Calculator to see how much diamonds actually cost based on the Four Cs.

Long's Diamond Calculator