What are the Four C's of a Diamond? 

Not all diamonds are created equal. Every diamond has its own grade, comprised of the Four Cs.

  • Cut
  • Color
  • Clarity
  • Carat

The Four C’s are the universal method for assessing the quality of any diamond, anywhere in the world. Basically, the Four Cs are how gemologists measure a diamond and can help you choose the one that’s right for you.

Diamond Cut

The cut of a diamond has the biggest impact on a diamond’s overall appearance, because it affects how well a diamond captures and reflects light back to the viewer's eye. In other words, cut is what makes a diamond sparkle.

The cut grade depends on the quality of a diamond’s proportions and symmetry. When a rough diamond reaches the hands of a diamond cutter, they create the shape and cut of the diamonds. A well-cut diamond will appear brilliant and sparkly, while a poorly cut diamond may appear dark and dull.

The pattern of surfaces (or facets) you see on a diamond represents the quality of the cut and has a direct effect on the overall sparkle of the stone. When a diamond well-proportioned cuts, light reflects from one facet to another, then reflects back through the top of the diamond.

Superior Cut DiamondSuperior Cut Diamond
Superior Cut Diamond
Shallow Cut Diamond
Deep Cut Diamond

If the cut of a diamond is too deep, some light escapes through the side of the stone. If the cut is too shallow, light escapes through the bottom of the stone before it can be reflected, thus reducing its brilliance.

The cut grading system rates diamonds from Ideal to Poor. The Gemological Institute of America (GIA) currently only grades round-shaped diamonds as Ideal, but that doesn’t mean you can’t get a great diamond in other shapes.

Diamond Color

D-F Colorless
G-J Near Colorless
K-M Faint Yellow
N-R Very Light Yellow
S-Z Light Yellow

Diamond color is actually measuring the lack of color. The less color in a diamond, the higher its value. The D-to-Z color-grading scale is the industry's grading system for measuring color. The scale begins with the letter D, representing truly colorless, like a drop of water, and continues, with an increasing presence of color to the letter Z, which may have a yellow or brown tint.

While D, E and F color grades are considered completely colorless, an untrained eye could not spot visible color in G, H, and I grades.

Diamond Clarity

Clarity is another way to refer to each diamond’s “flaws,” or its imperfections. Because every diamond is hand-cut, each will have its own small imperfections. Inclusions, birthmarks, blemishes — the natural identity marks within each diamond define its clarity.  The fewer imperfections a diamond has, the more valuable it is. The more imperfections (or inclusions) a diamond has, the lower the clarity.

The GIA International Diamond Grading System™ has a scale to measure diamond clarity, ranging from 0 (flawless) to 10 (included). When you’re shopping for a diamond, think about the clarity scale in terms of both quality and how visible imperfections will be to the naked eye.


These are flawless diamonds, no matter how closely you look.


These diamonds have very slight inclusions, visible only under a microscope. These inclusions are difficult for even a trained gemologist to see.

VS1, VS2

These are very slightly included, difficult to see with the naked eye and somewhat difficult to see under a microscope.

SI1, SI2

These imperfections can be seen by the trained eye under 10x magnification. They might still be visible to the naked eye, but harder to see in smaller stones less than 1c.

I1, I2, I3

Inclusions that are very easy for a trained eye to see under 10X magnification. These inclusions are often visible to the naked eye and in the case of I3 diamonds the inclusions may affect the structural integrity of the stone as well as impacting its brilliance.

Carat Weight

A diamond’s carat weight is the measure of its size.  Depending on the diamond shape, weight distribution and cut quality, two diamonds with the exact same carat weight can be different sizes.  Size is not everything – cut grade strongly affects the quality and beauty of your diamond.

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