THE 4CS NEVER APPLY EXACTLY THE SAME ON ANY TWO DIAMONDS: EVEN DIAMONDS WITH THE SAME GENERAL GRADING CAN HAVE DIFFERENT CHARACTERISTICS - EVERY DIAMOND IS UNIQUE.
The 4Cs are listed in descending order according to each Cs impact on the beauty and hence the value of the diamond.
The quality of the cut of a diamond is very important; it is what gives a diamond its unmatched brilliance and fire.
No matter what the diamond's shape is, a well-cut diamond will have the exacting proportions, symmetry, and finish for optimal light dispersion - called its brilliance.
A poorly cut diamond will not have the proportions, symmetry and finish for good light dispersion and will lose or “leak” light. These diamonds often look dull and lack “sparkle”.
There are three major components of cut; the diamond's proportions, its symmetry, and its polish. A well-cut diamond just explodes with light and fire.
The most prevalent cut is the round brilliant. Because all the perforations, angles and facet placements are equal around the circumference or girdle of the diamond it is also, technically, the most brilliant - evenly distributing the maximum amount of light return.
With all other diamond shapes, a small amount of light return is sacrificed for the art or style of the cut.
The edge or widest point on a diamond is called its girdle. A round brilliant has 32 facets and the table (large top facet) above the girdle – this part of the diamond is called the crown. Under the girdle there are 24 facets and the diamond's culet or point – this part of the diamond is called its pavilion. A modern round brilliant cut diamond has a total of 57 facets with the possibility of 58 if the culet is faceted instead of pointed.
The diamond's proportions are the relationship between the total depth (measured from the table to the culet), table, crown, pavilion and girdle and are expressed as a percentage of the diamonds average diameter.
The diamond's symmetry refers to the exactness of the outline, placement, alignment, and symmetry of the individual facets.
The diamonds polish is simply how well finished, smooth and free of polish lines and small blemishes the surface and individual facets are.
A standard round brilliant diamond’s overall Cut Grades, using GIA nomenclature is: Excellent, Very Good, Good, Fair, Poor.
Cut also refers to the shape of the diamond and what is required of the cutter to create the symmetry and proportions of that shape and style. The round brilliant cut is the most recognized style and shape - others are generally called Fancy. Fancy shapes or cuts include Marquise, Princess, Oval, Cushion, Emerald, Pear just to name a few.
The quality of a diamond's cut has a significant impact on its value. Poorly-cut diamonds often are sold for large discounts while a beautifully cut diamond will sell for a premium.
No matter whether you prefer a round brilliant, oval, marquise, emerald, pear or princess shape it is the quality of the cut that unleashes the fire and brilliance that nature has hidden inside every diamond.
Colorless or white diamonds are the most recognized and a completely colorless (or pure white) diamond is treasured for its extreme rarity and beauty. Color grading is determining the diamonds body color divergence from completely colorless.
A diamond's color grade is represented by letters starting with D, as completely colorless:
D, E &F are all colorless but E and F have very slightly less transparency.
G, H, I and J are considered near colorless; containing just a trace of color that often is not distinguishable to the eye.
K, L & M are faint yellow; the diamonds body color is starting to be seen by the eye. Some people find these diamonds warm body color desirable.
N to R are very light color; the diamonds body color is an easily seen yellow or brown tint.
S to Z are light color; these diamonds have increasing yellow or brown body color.
Many do not know that diamonds beauty can occur in a rainbow of colors. A fancy colored diamond is a very rare and uniquely beautiful gem.Vibrant yellows, deep rich browns, greens, pinks, light to strong rich blues, orange, purples, black and the rarest of the rare...red!
The most common fancy colored diamonds are the browns (sometimes referred to as champagne or chocolate diamonds) and yellows. For a diamond to be considered a fancy color it must have a body color that is greater than Z.
Fancy color is graded by increasing strength from Faint, Very Light, Light, Fancy Light, Fancy Intense, Fancy Vivid, Fancy Dark and Fancy Deep.
Keep in mind that each color grade is not a specific color or tint – it is a range of body color or tint. A diamond with an H color grade would have more color than a G and less color than an I – but two diamonds with an H color grade would not necessarily be the same exact color. The scope of each color grade increases as you go through the alphabet.
The clarity of a diamond is its fingerprint. Many diamonds have small internal or external irregularities or characteristics that were created when the crystal was formed or cut. These characteristics are called inclusions. The size, number, nature, and position of these inclusions determine the diamond's clarity.
Flawless (FL) & Internally Flawless (IF) - No inclusions visible under 10X magnification.
VVS 1 to VVS 2 - Inclusions are difficult to locate or see at 10X.
VS 1 to VS 2 - Inclusions less difficult to see or locate under 10X.
SI 1 to SI 2 - Inclusions readily seen at 10X, but remain invisible to the unaided eye when the diamond is viewed face up.
I1 - One or more inclusions, or their effect, can be seen by the unaided eye.
I 2 - Inclusions are so obvious that they affect both the brilliancy and beauty of the diamond.
I 3 - Shattered appearance or vivid disfiguring and dangerous inclusions and surface marks.
Just like with color grading each clarity grade is a range between the preceding grade and the grade immediately following. The scope of each clarity grade increases as you go down the scale.
The diamond's weight is the only C that does not have an impact its beauty. One carat is based on the weight of a carob seed. The tiny seeds from a locust (carob) tree are amazingly consistent in weight and for thousands of years, these seeds were used to balance gem scales.
Today a carat is a standard metric weight of 200 milligrams or 0.2 grams. There are 142 carats to an ounce. A carat is further divided into 100 parts called points. An example would be 0.50Ct. is fifty points or ½ a carat.
Diamonds are rare and large diamonds are very rare – the value of a diamond increases exponentially as the carat weight increases.