The Four C's of Diamonds

Much akin to snowflakes, diamonds are a natural wonder and no two are exactly alike. At National Jewelry Buyers, we professionally evaluate and price your diamonds off the criteria set by the Gemological Institute of America decades ago: the four C’s. Color, cut, clarity and carat weight are measurements used worldwide by diamond sellers and buyers both to communicate a diamond’s value more clearly. Our hope is that you, our valued customer, will use this post as a criteria to learn more about the magic numbers buyers like us use to better estimate the worth of your diamond! Class is now in session.

Clarity

It is a common misconception that diamonds are formed from super-heated chunks of coal and take millions of years to form. The truth is diamonds are formed when immense amounts of pressure, coupled with extreme heat, are applied to elemental carbon found inside magma deep within the earth, below the layer of mantle miles under the crust. This process normally takes anywhere from a few hours to a few days. Much better than waiting millions of years to find the right gem for your ring, isn’t it? This process forms pockets of carbon within the diamond rock called “inclusions” and these inclusions are what we use to judge the quality of a diamond’s clarity. Four words to keep in mind when having your diamond appraised in terms of its inclusions are “minute”, “minor”, “noticeable” and “obvious”.

Clarity is rated on a scale from FI (meaning flawless, without any visible inclusions or blemishes under magnification) to I-1, I-2 and I-3 meaning that the diamond has inclusions visible to the naked eye. To an untrained buyer a VVS1 diamond and an SI2 may appear very similar as the inclusions would be too small to detect. Inclusions can be white or black in color and can be found anywhere around the outer edge or inside the diamond. If your diamond is graded as an “SI” or “I” quality, don’t worry: your diamond still holds worth! Keep in mind that less than 0.001% of diamonds are ever graded as “Fl” or “IF”.

 

Color

 

When referring to a diamond’s color, we are actually looking into its lack of color. A higher-quality diamond will have no hue or tint and look almost like a drop of water whereas a lower-quality diamond will appear yellowish underneath a grading light. Like every other professional business in the industry, NJB uses the GIA’s “D-Z color grading scale” when judging the color of a diamond. Much like the academic grading scale, a higher letter means a better grade, a clearer (and more valuable) color of diamond.  

 

 

 

As you can see from the chart, it is much easier to judge a diamond’s color either through its sides (girdle) or bottom (pavilion) rather than down through its top (table). Like inclusions in clarity, small differences in color can mean a big difference in value. Another word to keep in mind when finding a diamond’s color is “fluorescence”. Fluoresence occurs inside a diamond when carbon gas escapes during the solidifying process of the rock within magma, which can make a diamond’s color appear a better grade than it truly is. Roughly 50% of diamonds contain fluorescence and the visible amount of it can be easily seen with ultraviolet light. The more blue and/or purple seen in a diamond under UV light, the more fluorescence it contains.

However, not all color in diamonds is a bad thing! Some diamonds come in red, orange, yellow, green, blue, etc. and are graded as “fancy” diamonds. If your diamond is graded as “fancy”, this means that the color of your diamond has actually added significant value!

 

Cut

 

 

Of the four C’s of diamonds, cut is without a doubt the most important. A “K” color diamond with a superior cut than a “D” color diamond, or an SI1 with a better cut than a VVS1 makes it much more valuable! If you’re asking yourself “how?” remember that a cut diamond’s purpose is to show of its brilliance. When light hits a diamond, part of this light shines back to the observer through a process known as “external refraction”. External refraction has three different measurements: brilliance (white light), fire (colored light) and scintillation (the pattern of light and dark light a diamond creates which causes it to sparkle).

Notice the difference between white and colored light in this diamond.

 

 

The more obvious kind of “cut” in a diamond is its shape. Round cuts, as pictured above, are by far the most common kind of cut and often the most valuable as it is easier to set them into jewelry. Pears, hearts, emeralds, princess square, baguette, marquise and oval cuts are other common kinds of cuts for diamonds and other gemstones.

 

 

Carat

The fourth and final “C” in diamond grading is the first one everyone notices when looking at a diamond and simply means how large (and therefore how heavy) the diamond is. Most diamonds are commonly found between the 0.25 carat (one-quarter) and 1.00 (one) carat weight range, however diamonds can vary anywhere from 0.05 carats to upwards of four, five, six or more carats.

 

 

A 0.50 ct. diamond is roughly the size of an earring clasp.

 

All else being equal, a larger diamond is more rare and desirable, and therefore more valuable. However, a diamond of a larger carat size can still be worth less than a smaller diamond of superior cut, color and clarity. There are also “magic numbers” in certain diamond sizes including 0.50 ct., 0.70 ct., 0.90 ct., 1.00 ct., and every half-carat after. While a 0.94 ct. and 1.00 ct. diamond may not appear much different, the slight change in size could make all the difference in value.

 

 

It’s very important to keep all of the four C’s in mind when selling your diamond or purchasing a new one. A slight difference in any of the four could mean a huge different in value! We hope you can use this summary to help you get a better idea of the value of your diamond and one of our professional buyers would be more than happy to guide you through it, and your diamond, with you in our stores!