Every diamond, like every snowflake, is unique. Diamonds differ from one another in any one of four categories, referred to as the 4C’s – Carat Weight, Clarity, Color, and Cut. Using the 4C’s as criteria, gemologists grade each diamond to determine its value.
The diamond market has defined several different “magic weights” for diamonds, which impacts the price. A “magic weight” is the weight at which the value, or cost, per carat of the diamond increases. For example, a diamond that weighs 0.98ct can have a significantly lower cost than one that weighs 1.00ct, with all other factors equal, because 1.00ct is a “magic weight”. When shopping for a loose diamond, ask for the specific weight to verify that the price is relative to the exact carat weight.
As the weight of a diamond increases, so does the price per carat.
Therefore, the better the clarity, the more the value, and gemologists classify clarity using these eleven grades:
Flawless diamonds show no blemishes or inclusions when examined by a skilled and experienced grader under 10x magnification.
The following do not disqualify a stone from the flawless category.
IF stones show no inclusions and only significant blemishes under 10x magnification. normally what separates IF from FL stones are characteristics that can be removed by minor repolishing (light surface graining is an exception).
VVS diamonds contain minute inclusions that are difficult for even the skilled grader to locate under 10x magnification. In VVS1, they are extremely difficult to see, visible only from the pavilion , or small and shallow enough to be removed by minor repolishing. In VVS2, the minor inclusions are very difficult to see.
VS stones contain minor inclusions ranging from difficult (VS1) to somewhat easy (VS2) for a trained grader to see under 10x magnification. Small included crystals, small feathers, and distinct clouds are typical.
SI stones contain noticeable inclusions which are easy (SI1) to very easy (SI2) to see under 10x magnification. In some SIs, inclusions can be seen with the unaided eye.
I1, I2 and I3 (Imperfect)
I-grade diamonds contain inclusions which are obvious to a trained grader under 10x magnification, can often be easily seen face-up with the unaided eye,
seriously affect the stone’s potential durability, or are so numerous they affect transparency and brilliance.
The most popular color range is “Near Colorless” because diamonds in this range are more affordable, and when mounted can appear just as colorless as
diamonds in the “Colorless” range. Typically, less color equals greater rarity, increasing the value of the diamond. But, the natural presence of a fancy color can
result in a cost that is more than a colorless, all things being equal. An example of a fancy color diamond is the famous Hope Diamond, which is a beautiful dark
Style – Diamonds are cut into many shapes and the shape is the most recognizable attribute to most people.
Facet arrangement is a little less common. Most diamonds have one of three basic facet arrangements: brilliant, step, or mixed. Brilliant cut diamonds have a facet pattern that radiates from the center of the stone toward the edge with triangle or kite shaped facets, ex: Round Brilliant. Step cut diamonds have concentric rows of trapezoidal facets running parallel to the girdle, ex: Emerald Cut. A mixed cut diamond combines both brilliant cut facets and step cut facets; often this style is seen as a diamond with a step cut crown and a brilliant cut pavilion. Mixed cuts are not common.
Make – Whatever the shape, a well-cut diamond is the work of a master diamond cutter. When cut to good proportions, a diamond is better able to handle light, creating more scintillation, or sparkle. Although many cannot see an actual difference in cut, they can appreciate and recognize the beauty of a well-cut diamond. It is the cut that enables a diamond to make the best use of light.
How a Diamond Handles Lights:
1. When a diamond is cut to good proportions, light is reflected from one facet to another and then dispersed through the top of the stone.
2. If the cut of the diamond is too deep, some light escapes through the opposite side of the pavilion.
3. If the cut is too shallow, light escapes out the pavilion walls before it can be reflected.
Anatomy of a Diamond Diagram
|Birth Month||Stone||Alternate Stone|
|1||Gold Jewelry||Fresh Water Pearl||18||Cat’s-Eye Chrysoberyl||Opal|
|7||Onyx||Copper, Lapis Lazuli||24||Tanzanite|
|8||Tourmaline||Aventurine, Bronze||25||Sterling Silver|
|9||Lapis Lazuli||Tiger Eye||30||Pearl||Diamond, Jade|
|14||Opal||Gold, Ivory, Moss Agate||55||Alexandrite||Emerald|