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Can you ever ignore the 4 Cs?

If you’ve starting shopping for diamonds, you’ve probably heard of the vaunted ‘4 Cs’. These are the basic criteria upon which diamonds are graded. Many will tell you that these are absolutes, never to be ignored. They are certainly important, but can you ever set one or even all of them aside? The ‘Cs’ in diamond grading stand for clarity, cut, colour and carat weight.

Here’s what each one really means in terms of a diamond and its value.

  • Almost every diamond has some flaws or inclusions, even the ones graded as ‘flawless’. These imperfections alter the direction of light as it passes through the stone. Some are big enough to see without assistance from a loupe or microscope; some are nearly undetectable, even with 10 times magnification. The fewer and smaller the flaws, the higher the grade on clarity.
  • The way a diamond is cut will give it the sparkle and reflectivity that makes these stone so desirable. The better the cut, the more light will bounce around inside the stone, making it glisten and glow.
  • Even diamonds that appear to be as clear as glass have a colour. Others can have distinct tints and hues ranging from nearly colourless to shades of yellow, blue, pink or even black. The less colour a stone has, the more rare and, therefore, more valuable it will be.
  • Carat weight. This simply indicates the size of the stone by weight, not the top surface or visible portion of the stone in the setting.


See for yourself

Now you know how gemologists determine the grade of the diamonds that you will be shown when you visit your jeweller. While these factors will tell you a great deal about a diamond, they don’t tell the whole story. Your own eyes can also tell you a lot!

Clarity: A diamond will have some flaws. The clarity ratings will have a lots of descriptive words for the inclusions, such as cloud, needle, pinpoint or haze. Stones with flaws that you can’t see with your own eyes are almost all pretty good stones. Even a stone with a small flaw in an unobtrusive place that you can barely make out can be a good value.

Cut: This C has perhaps the greatest influence on the way it looks in the setting and on the wearer. It’s not just the general shape of the diamond (brilliant, marquise, princess, emerald cut, etc.), but the way the stone is faceted and polished. What we call sparkle, diamond cutters call light performance. There are subtle differences in the top grades, but the difference between an ‘ideal’ and a ‘poor’ stone – even of the same size, clarity and colour – will be obvious.

Colour: When you’re looking at nearly colourless stones and not ‘fancy’ colours like blue or pink, you may not be able to perceive the difference in colours. Most of the near-colourless categories will only have a slight warm or cool cast to the untrained eye. This understated shading towards one end of the spectrum or the other may appeal to your eyes.

Carat weight: Carats will tell you the weight of the stone only. It won’t tell you which stone has the biggest surface area. Most people evaluate the size of a diamond’s table (what you see as it’s viewed from the top) and not how deep it goes into the setting. It’s like saying a person’s weight – 150 pounds can look portly on one and svelte on another. The price can also drop significantly with a tiny change in carat weight. A .9 carat may cost a good deal less than a 1.0 and look better in the setting.


So, consider all 4 Cs when choosing you diamond, but also consider how the stone looks to you. Both are important to getting the look you want.

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