Know your Diamonds

The Story of Diamonds

Every diamond is a miracle of time, place, and chance. Like snowflakes, no two are exactly alike.

The formation of a diamond requires a unique combination of natural events. Most diamonds were created 160 or so kilometers (100 mi) below the Earth’s mantle. At that depth, extreme pressure and heat worked in unison to transform pure carbon into diamond crystals. The combination of heat and pressure does not exist everywhere, which is one of the reasons natural diamonds are so rare.

Diamonds have been in demand for thousands of years, but until the mid-twentieth century there was no standardized method of assessing diamond quality. The Gemological Institute of America (GIA) developed a universally agreed-upon system to judge the quality of a diamond:  The 4Cs.  Today, a customer anywhere in the world can clearly understand the Color, Clarity, Cut, and Carat Weight – all of which help determine the value of a diamond – using the 4Css.

How Do I Choose the Right Diamond?

Of all the 4Cs, carat weight is the one customers tend to focus on the most. When you are deciding on the carat weight of a diamond, bear in mind the size of your hand, and the size of the setting, and your budget. You may find that the cut, color, and clarity of a smaller diamond is more suited to your taste and a specific carat weight is not important to you. Keep in mind that the smaller the finger, the larger the diamond will appear. A 1.5-carat diamond solitaire will appear much larger on a size 5 finger than it will on a size 8. If your heart is set on a large carat weight and you need to stay within a budget, the perfect diamond for you could be one rated at SI clarity, G or H color, and “good” cut. Diamond prices jump at the full- and half-carat weights. Diamonds just below these weights cost significantly less, and small size differences can be almost impossible to detect.

Learning what the 4Cs tell you about the appearance of a diamond and how they affect its value will help you make an informed decision about your jewelry investment.

The 4Cs  Cut

When we think of the cut of a diamond, we usually think about which shape we want. The 4Cs, however, grade the cut of a diamond based on how well facets interact with light. Generally a diamond is cut with 58 individual facets.  Precise mathematical formulas determine how to best cut an individual gemstone to maximize the amount of light reflected through the diamond and to increase its beauty.

Factors that affect the grade of a diamond’s cut include overall dimensions, the quality of the workmanship, and the finish.  Regardless of the final shape, all cuts are defined by the same characteristics:  Table diameter, crown height, girdle thickness, and pavilion depth.

Many people begin choosing a diamond based on the shape they like best. The classic, round brilliant cut is the standard by which all diamond shapes are graded. “Fancy” refers to any other cut: oval, princess, marquise, pear, radiant, emerald cut, and heart shaped are the most popular “fancy” shapes.  The shape of a diamond can make a dramatic difference in the price and look of a stone.

The round brilliant-cut diamond is by far, the most popular and most researched diamond shape available today. The fire of a brilliant-cut diamond is unmatched, which tends to make it the most valuable cut..

The brilliance of an oval diamond is similar to a round diamond, which makes oval diamonds a very popular choice. The shape is particularly flattering on long slender fingers.


The square shape and pointed corners of a princess cut diamond capture and reflect light in a uniquely brilliant fashion.  This eye-catching shape is a favorite choice for engagement rings.


The elegant lines of a marquise diamond highlight the carat weight, helping the stone look larger.  Marquise-cut diamonds pair well with different accent stones, inspiring wonderfully creative jewelry designs.


Also known as a teardrop, the single point and rounded end of the pear shape works well in a variety of jewelry. Earrings with pear-cut diamonds are especially captivating, and a pear-cut diamond ring subtly slims the finger.


The radiant-cut diamond is a dramatic rectangle with distinctive, trimmed corners. Radiant-cut diamonds lend themselves well to multi-stone eternity bands and “tennis” bracelets.”  Because the standards of a radiant-cut allow the proportions of the rectangle to vary, a piece of jewelry with expertly matched radiant-cut diamonds is sure to be a treasured gift.


An emerald-cut diamond sparkles like no other, thanks to rectangular facets on the pavilion (lower section of the stone.)  A large, smooth table (top surface) accentuates the clarity of a diamond. The long lines and shimmering surfaces of an emerald-cut diamond capture light for a brilliant effect .


The heart-shaped diamond is an iconic symbol of enduring love.  A modified brilliant cut, the heart shape is meticulously crafted with a double-rounded top and pointed bottom.  Popular as a solitaire pendant, a gift of heart-shaped diamond jewelry will truly tell someone how special they are to you.



The 4Cs – Carat

Diamond weight is measured in carats and can range from below 0.01cts all the way up to hundreds of carats.  Carat weight, taken into account with the other 4Cs, is a deciding factor in pricing.

The carat is a unit of mass equal to 200 mg.

The 4Cs – Color

No color is the ideal color grade of a perfect diamond. The color of a diamond is what determines how light is reflected. A colorless diamond reflects the full spectrum of the rainbow. Color ratings begin with the letter D, indicating the finest colorless diamond. From D, ratings descend the alphabet to Z, indicating a diamond of light yellow, brown or gray. An absolutely colorless, grade D diamond is extremely rare, so it’s good to know that not even trained experts, unless under ideal laboratory conditions, can see the difference between one color grade and the next. This fact helps make color grades G-I excellent values.

Color grades generally fall into the following categories:

D: Absolutely colorless.  Extremely rare

E-F: Colorless.  A rare diamond, these stones have minute traces of color only detectable by trained gemologists.

G-H: Near colorless. A trained expert is able to distinguish the difference between G-H diamonds and diamonds of higher quality only by comparing them side by side. These diamonds are generally an excellent value.

I-J: Near colorless.  The only color present in these diamonds is a slightly detectable warm tone. Diamonds rated I-J offer exceptional value.

K-M: Noticeable color.  At the K level, pale tints of yellow begin to be visible to the naked eye. These diamonds are much less expensive and, in the proper setting, can be appealing.

N-Z: Diamonds in this color range have easily seen color and are not commonly available.

Diamonds with natural color (pink, blue, yellow, and others) are known as “fancies” and can be quite rare.  A different set of standards is used to grade the color of fancy diamonds: fancy vivid, fancy intense, and fancy light. Fancy-vivid diamonds are the rarest and the most expensive.

 The 4Cs – Clarity

Virtually all natural stones have some inclusions. Clarity indicates how inclusions affect the quality and appearance of a diamond. The size, location, and number of inclusions determine the clarity grade of diamond. Clarity is graded on a scale from FL (internally flawless) to I (included.).  The standards for clarity are:


Flawless (FL)No inclusions or blemishes are visible to a skilled grader using 10x magnification
Internally Flawless (IF)No inclusions and only blemishes are visible to a skilled grader using 10x magnification
Very, Very Slightly Included (VVS1 and VVS2)Inclusions are difficult for a skilled grader to see under 10x magnification
Very Slightly Included (VS1 and VS2)Inclusions are minor and range from difficult to somewhat easy for a skilled grader to see under 10x magnification
Slightly Included (SI1 and SI2)Inclusions are noticeable to a skilled grader under 10x magnification
Included (I1, I2, and I3)Inclusions are obvious under 10× magnification and may affect transparency and brilliance


Diamonds from a reputable jeweler will always be accompanied by certification.  The certificate documents carat weight, cut grade, color grade, clarity grade, measurements, and physical properties, as well as plotting diagrams showing the inclusions.

Certificates are issued by recognized gemological laboratories. Among the most well-known are the GIA (Gemological Institute of America), the IGI (International Gemological Institute), the HRD (High Diamond Council – Hoge Raad Voor Diamant), the SGL (Solitaire Gemmological Laboratories) and the IDL (International Diamond Laboratories).

Every piece of diamond jewelry that offers includes certification.