The 4 C’s of Diamonds: What’s Most Important?

The 4 C’s of Diamonds: What’s Most Important?

In the same way you would check the Blue Book value of a car before you buy it, or the ratings of a high-end restaurant before you book a reservation, there are comparisons you can make in the quality and value of diamonds based on their grade. Let us first say that the process we feel is best is to actually show you - in the store - a variety of diamonds at difference grades and carats weights, letting you experience the difference - the things you notice and don’t notice - allowing you to determine which diamond is right for you. If you want to be sure you are getting the best quality when purchasing a diamond, it is important that you know as much as possible about how diamonds are classified. And once you fully understand how diamonds are classified, you can use that to your advantage, learning how to find a beautiful diamond within your budget. The “Four C’s of Diamonds” refer to the stone’s color, clarity, carat (weight or size) and cut. The four C’s are the primary criteria the American Gem Society use to grade gems and determine their value and price. Each “C” has its own grading scale, which helps sellers determine the price of the diamond and shoppers to determine the best fit for their needs.


solitaire diamond, engagement ring, evansvilleMost diamonds, although appearing colorless, actually have slight tones of yellow or brown. As these tones become more easily apparent, the rarity and cost decrease. The market traditionally valued white diamonds higher than others, and the grading scale according to color reflects that. The D grade, is considered colorless, rarest and most expensive. Going down the 23-scale grade from D to Z, diamonds becomes progressively more yellow or brown. Most diamonds you see at the store are considered “near colorless,” or between G and J on the color scale. At a J grade and beyond, the human eye can start to detect a yellow tint. It is rare that you will find a D grade diamond, and if you do, it may break the bank. If you’re worried about your budget, moving down the color scale toward H and I lets you buy a diamond that still appears white, but is much more affordable.


It is important to remember that diamonds are a thing of nature, and like most things in nature, they are rarely perfect. 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 and work around them, but often, they are still there- and the clarity grade of a diamond is what measures them. The scale ranges from flawless to heavily “included”:

  • F: flawless inside and out
  • IF: internally flawless, which means there are blemishes on the surface, but not inside the diamond
  • VVS1 and VVS2: very, very slightly included
  • VS1 and VS2: very slightly included
  • SI1 and SI2: slightly included
  • I1, I2 and I3: included

It is often difficult to see inclusions with the naked eye unless you look closely, depending on where they are located on the diamond. Every diamond is different, though. If you look at an SI2 diamond and personally can’t see the inclusions without a jeweler’s microscope, you can probably accept a lower grade and save on cost without compromising the diamond’s beauty. 


People often mistake carats as a measurement of size, but they actually measure weight. Diamonds are also measured in points. 100 points equals 1 carat of weight. You will often see the abbreviation “ctw,” which means “carat total weight.” This measures the total weight of all diamonds in a piece of jewelry. It’s crazy to believe, but a very small difference in carat weight can sometimes result in a spread in cost. To the eye, the difference between a 1.1-carat and a 1.2 carat diamond (1 1/10 carat and 1 ⅕ carat diamonds) might be impossible to discern, but the cost difference between those carats can be thousands of dollars. If you’re wanting to shave off cost on a diamond, start by looking at a diamond 10 to 15 points less than a diamond you like. For example, if you love a 1.6-carat diamond, see what it looks like next to a 1.5-carat diamond of the same quality. It’s likely you’ll have difficulty seeing a big difference, but you may end up saving hundreds of dollars.


marquise diamond, evansville, engagement ringA diamond’s cut is harder to quantify than color, clarity and carat weight. The reason is because cuts can vary from diamond to diamond and have to do with how the diamond cutter chooses to shape, facet and polish a diamond. Sometimes diamonds are cut so that they are heavier, thus fetching more value for their carat weight. And sometimes they’re cut to hide or minimize inclusions. Cut is so important that several brands have actually patented their own type of cut. Many women and men come through our doors looking for a Hearts on Fire diamond, the World’s Most Perfectly Cut Diamond ©. This claim has actually been backed up in court. The Fire & Ice brand, whose special cut delivers a “bigger, brighter, whiter” appearance, also stakes their claim on an exceptional cut. Because diamonds are essentially a prism of light, ideal cutting of a diamond dramatizes the rare splendor of a diamond to produce dazzling-brilliance. When done well, a diamond’s cut can easily be considered the most important C.  

How to use the four c's to your advantage

Now that you understand the 4 C’s of diamonds, you can learn to use them to your advantage. As you are starting to compare diamonds and trying to work within your budget, consider how you might:

  • Get a beautiful, sparkling diamond by focusing on the cut while sliding down the scale a few levels on color and clarity.
  • Get a larger diamond, but scale back a fraction of a carat (10-20 points) to save money.
  • Buy a lower weight diamond but a near-ideal or ideal cut, focusing on the diamond’s radiance and beauty and putting less emphasis on the size.

  The 4 C’s of Diamonds will reassure that you’re buying a quality diamond and getting what you pay for, but remember they are just a tool. Rather than bragging about her “1-ct. E VS1” diamond, your fiance will exclaim, “He proposed! Look at my beautiful engagement ring!” And that’s ultimately what’s most important.

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