Understanding the Four C’s of Diamonds

Posted by Nate Barsky on

When grading diamonds, the jewelry industry uses criteria often referred to as the four C’s of diamonds. The C’s stand for:

  1. Cut
  2. Clarity
  3. Color
  4. Carat weight

A fifth “C” to consider is “certificate,” which comes with all of Barsky’s diamonds. Certificates certify the quality and dimensions of the diamond and the appraised value, which is important for insurance and other financially related items.

Let’s explore the four C’s of diamonds in more detail to help you understand your engagement ring.

Cut: where the sparkle is defined

The most important thing to know here is that the cut is not the shape. The cut refers to the reflective quality of the diamond. Think of the cut as the sparkle of the diamond. This is one of its most important qualities. The cut of the diamond will have a direct impact on its pricing. Diamonds that reflect all the light that enters will be the most expensive. It is estimated that only 3% of diamonds allow this type of reflection.

Those that allow less light in will be slightly less expensive and are referred to as very good or good cut. They have exceptional beauty and are a great value for the money.

Barsky’s carries diamonds that feature a high quality cut with exceptional polish not found in most other stores. Some of the terms you will hear or see mentioned are:

  • Ideal Cut
  • Very Good Cut
  • Good Cut
  • Fine Cut
  • Deep Cut

For the untrained eye it would be very difficult to see the difference between an ideal cut and a good cut.

Clarity: nature isn’t perfect, and neither are diamonds

The clarity of a diamond is defined by the number of natural imperfections. Many of these imperfections are microscopic in nature and very hard to detect by anyone but a professional.

You may hear a jeweler refer to these imperfections as blemishes and/or inclusions. There is a difference between the two:

  • Blemishes are surface flaws
  • Inclusions are internal flaws

The diamonds with the smallest imperfections will receive the highest clarity scores. The following grades are applied to the clarity of a diamond:

  • FL, IF = Flawless and Internally Flawless
    These diamonds are exceedingly rare and command high prices.
  • VVS1, VVS2 = Very Very Slightly Included
    This type of imperfection is very difficult to see unless magnified at least 10x.
  • VS1, VS2 = Very Slightly Included
    Imperfections are not usually visible to the untrained eye.
  • SI1, SI2 = Slightly Included
    These imperfections are visible under 10x magnification.
  • I1, I2, I3 = Included
    These diamonds have imperfections which are visible to the eye. Barsky Diamonds does not sell or stock these diamonds.

When shopping for your engagement ring, you should look at those diamonds with VVS and VS grades as your first choice, then the SI grades. The Slightly Included diamonds are a great value for your money, and the flaws cannot be seen unless someone takes out a very powerful magnifying glass.

Color: colorless diamonds are the most desired

The color of a diamond determines its whiteness. Jewelers grade diamonds on a scale from D to Z, with D being the highest possible color rating. What this simply means is that the less color a diamond has, the higher its rating will be. So a colorless diamond, which is rare, is typically as a D.

Diamonds rated from D to I will show virtually no color to the untrained eye. Diamonds rated from J to M will have a very faint tinge of yellow to them. You can minimize the color of the diamond with an appropriate setting, and some people do prefer the slight warmth of color. However, our most popular diamonds show virtually no color and always dazzle. Your future bride is guaranteed to love it.

Also keep in mind that the color of the diamond is more noticeable in larger diamonds, especially in those over two carats.

It’s important to know that this color rating does not apply to colored diamonds. This type of diamond could be anywhere from blue or green to yellow and are rare and extremely expensive.

diamond color

When considering the color of a diamond, you may also run across the term “fluorescence.” The fluorescence of a diamond refers to the glow that the diamond can emit after being subjected to certain light conditions, normally ultraviolet lights.

Carat: measuring the size of a diamond

The carat of the diamond simply refers to its weight. One carat is equal to 2.0 grams or 100 points, so if you want to purchase a 1⁄2 carat diamond then you should look for one with 50 points. When looking at the carat size, you should also take a few other points into consideration:

  • The distance across the top of the diamond
  • The diamond’s cut grade
  • Your future bride’s preference for large or showy jewelry

Looking at the distance across the top of the diamond is important, as this is the way you would normally view the diamond in its setting. The way the diamond is cut affects the way it looks.

A well cut diamond that reflects lots of light will appear bigger. If you were to choose a larger diamond with a lower quality cut, the light will not reflect as well, making the larger ring actually appear smaller.

When determining which carat weight to buy, take into account the ring setting and the size of your fiancé’s finger. A one-carat diamond is going to look larger on a size 4 finger than on someone with a size 6 or 7 finger.

Certificate: diamond certificates allow you to buy with confidence

A diamond certificate is simply a record of your diamond. The certificate will list the exact details of the weight along with its measurements. It will also list the characteristics of the diamond and is used as proof of a diamond’s identity and value.

Certificates for diamonds are issued by an independent third party, such as the Gemological Institute of America (GIA), one of the most respected diamond laboratories in the diamond industry. Some other certification laboratories you may come across include EGL, AGS, and IGI. Viewing the certificate will give you confidence in knowing the specifications of your diamond before you buy.

One important thing to remember about buying a diamond is that you need to see the diamond with your own eyes, because the ultimate decision will depend on your taste and what appeals to you personally. Barsky Diamonds offers a large inventory of loose diamonds to choose from and specializes in GIA-certified diamonds.


I’m Nate Barsky, one of a long line of Barskys who have been creating diamond engagement rings in Philadelphia’s famous jeweler’s row for over 100 years. I’d love to help you find your perfect engagement ring: Get in touch today so we can help you find the perfect ring for you.