4C’s Diamond Buying Guide: How to Buy a Diamond

Each of the 4 C’s (Cut, Colour, Clarity, and Carat) plays a role in a diamond’s beauty, though it is difficult to decipher one component by itself. Put together, the diamond 4Cs help diamond sellers determine the price and compare diamonds to one another. They’re also a useful tool for shoppers — and the more you understand about them, the savvier you’ll be in choosing your diamond. Once you fully understand the 4Cs of diamonds, you can use them to your advantage to find a beautiful diamond within your budget.

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. Without finding the right balance between the 4cs, you will end up overpaying for certain characteristics while not spending enough on others.

So, here are the most important characteristics to understand when making a diamond purchase.


The cut is the only diamond component not influenced by nature, and it’s the most important of the 4Cs. Diamonds are cut to maximize the sparkle, fire, brilliance, and overall visual beauty of a diamond. The cut is a measure of light performance as light hits a diamond. Diamonds sparkle is a result of light performance.

As light hits a diamond, it penetrates the diamond, bounces around, and reflects within the diamond and ultimately returns light to your eye. That is the sparkle that you see. The cutting of a diamond directly impacts the amount of light performance achieved. The angles, locations, sizes, and shapes of facets will determine the diamond sparkle.

When selecting a diamond, it will certainly important to ensure the light is not lost. Excellent cuts are the most premium and Very Good cuts offer more value. The differences in sparkle are quite subtle, but they are noticeable when compared side by side. We recommend maximizing the Cut grade, if possible.


The perfect diamond is colourless. Diamond Colour is graded in terms of how white or colourless a diamond is. The pricing of diamonds usually reflects these grades—sometimes significantly. In most cases, the naked eye cannot tell the difference between two adjacent colour graded diamonds, though the price difference may be significant.

Diamond colours fall under a D-Z scale, with D meaning completely colourless (and the most expensive), and Z having a light-yellow hue. A round brilliant diamond, for example, hides colour incredibly well, meaning you can go further down the scale without seeing any yellowing. However, longer diamond shapes, like oval and radiant, reveal colour much easier.

It’s also a wise move to consider the colour of precious metal for your setting that best compliments the colour grade of your diamond. For example, yellow gold casts a warm glow and looks best with diamonds with faint colour. Platinum or white gold will make a near-colourless diamond look icier.


Like any rock or mineral, diamonds often have flaws, known as inclusions and blemishes. Diamond cutters try to cut and polish a diamond to hide these inclusions or work around them, but they’re still there. And, the Clarity grade measures them & evaluates how clean a diamond is from both inclusions and blemishes. Inclusions are extremely common within diamonds and are essentially birthmarks that give every diamond uniqueness.

Clarity is the third most important characteristic because most imperfections cannot be seen unless under at least 10 times magnification. Choose an eye-clean diamond. Blemishes and inclusions should not distract from the brilliance or fire of a diamond.


Often when people hear the term “Carat Weight,” they think it refers to the size of the diamond. Instead, it refers to a measurement of the actual weight of the diamond. Naturally, the larger the carat, the more expensive the diamond. Sometimes, very small differences in carat weight can result in a disproportionate spread in cost.

Carat weight is not related to sparkle. Beautiful sparkle is the result of a well-crafted cut. A high carat weight diamond with a poor cut may look smaller than a diamond with the smaller carat weight and a very good cut.

Every diamond is unique, and there are a variety of factors that affect the price of a diamond. After learning about the 4Cs, if you need to see diamonds in person, visit your local store. Get a better sense of what you value in a diamond. Focus on the factors that are most important to you, and choose a diamond that satisfies your standards for beauty and value.