Buying a diamond should be a great experience and one that is not confusing or overwhelming. Like any other large purchase you make, education and knowledge is key. Before purchasing your diamond make sure you have at least a basic understanding of the 4Cs, diamond shapes, diamond terminology, and what to look for on a diamond grading report. This will prepare you to ask the right questions and will give you the confidence that the decision you make is the right one for you.
The 4Cs of Diamonds: Cut, Clarity, Carat Weight, Color
Of the 4Cs, Gemologists believe that cut has the greatest influence on a diamond’s beauty. Cut is the factor that determines the diamond’s fire, sparkle, and brilliance. Diamonds have a unique ability to effectively manipulate light. This unique quality can only be realized with an extremely high level of accuracy during the cutting and polishing process. Where nature dictates the uniqueness of color and clarity, humans affect the cut. While cutting diamond rough, cutters must not only consider the proportions of a diamond, but also the craftsmanship of overall symmetry and polish as well.
A diamond’s brilliance comes from light entering the crown and reflecting from one facet to another and returning back out the crown. A diamond that is cut too shallow or too deep will not reflect light properly and the diamond will not be as brilliant as a diamond with an excellent cut.
Clarity refers to the absence of clarity characteristics in the diamond. The GIA clarity scale consists of 11 grades ranging from flawless to included. When determining a diamond’s clarity grade, GIA considers the size, nature, color, position, and quantity of clarity characteristics under 10x magnification. The lesser the number of inclusions or blemishes a diamond has the higher clarity grade it will receive. A diamond with no inclusions using 10x magnification will be considered flawless and is very rare and more costly.
An inclusion is a clarity characteristic either totally enclosed in a polished diamond, reaching or extending into it from the surface, or one that is caused by treatments or the cutting process. Note – Inclusions caused by treatments or the cutting process may not always be documented on the diamond certificate.
A blemish or external clarity characteristic is on the surface of the diamond only and can be caused by wear, the cutting process, or may be a result of the diamond’s crystal structure. Blemishes play a lesser role than inclusions do when determining the clarity grade, but may affect the polish grade.
GIA Clarity Grades
FL – Flawless – no blemishes or inclusions under 10x magnification.
IF – Internally flawless – no inclusions and only very minor surface blemishes.
VVS1 and VVS2 - Very, very slightly included – very, very small microscopic inclusions extremely difficult to see under 10x magnification.
VS1 – Very slightly included – very small microscopic inclusions difficult to see under 10x magnification.
VS2 – Very slightly included – very small inclusions somewhat easy to see under 10x magnification. These diamonds represent a good value to someone looking for a high quality diamond, as the very small imperfections do not affect the beauty of the diamond.
SI1 – Slightly included – small inclusions that are easy to see under 10x magnification. This clarity is an excellent choice for someone looking to stay within a budget, but wants a diamond that will look as good as a higher clarity diamond except when viewed under magnification.
SI2 – Slightly included – small inclusions that are visible under 10x magnification. Depending on their location within the diamond, they may sometimes be visible to the unaided eye without magnification. SI2 diamonds are attractively priced and typically no visible difference can be seen without magnification. If you are interested in an SI2 diamond and would like us to personally verify if it is eye-clean, please give us a call at 1-800-979-1910.
I1* and I2 – Included – imperfect with inclusions that are obvious to the unaided eye and may affect the diamond’s durability.
I3* – Included – imperfect with inclusions that are extremely obvious to the unaided eye and pose a definite threat to the diamond’s durability.
*At Since1910.com, we do not sell I1, I2, and I3 clarity diamonds.
Diamond Carat Weight
Carat weight refers to the size of the diamond. Carat is the standard term used for the weight of a diamond and received its name from the seed of a carob tree. The carob seeds were used by early diamond traders on scales as units of weight for small amounts of diamonds because of their consistent size. The weight of the carob seed was 200 milligrams and the weight of a carat is exactly 200 milligrams or as it is know today, 0.2 grams
Many believe that the term carat represents the size of the diamond however; carat represents the weight of a diamond. One carat is divided into 100 points. So, for example, a quarter carat or 25 point diamond weights .25 carats (cts). Diamonds weighing over one carat are expressed as carats and decimals. They are measured to the hundred thousandths of a carat and rounded to a hundredth of a carat. For example, a 1.25 stone would be described as one point twenty five carats.
The cost of a diamond is not measured in weight alone. Several diamonds of the same weight can be priced considerable different. When calculating the cost of any diamond, clarity, cut, and color are major factors as well.
Color refers to the absence of color in the diamond. Diamonds composed of pure carbon are colorless and extremely rare and costly. Most diamonds contain nitrogen, boron, or hydrogen all of which impact color. A majority of white diamonds sold on the market today contain traces of nitrogen, which causes slight shades of yellow or brown. Small, subtle differences in color can make a substantial difference in a diamond’s value.
In a effort to eliminate confusion related to diamond color, the Gemological Institute of America (GIA) implemented the color grading system in the 1950s which is still being used industry wide today. Diamonds are graded on a scale beginning with the letter D (colorless) and ending with Z (light yellow or brown). When creating the new color scale GIA chose to start with the letter D as a means of starting over. Prior to GIA implementing the D-Z scale, other systems all of which were inconsistent and inaccurate, already used the letters A-C, numbers 0-3, and the Roman numerals I-III. It is important to note that diamonds at the end of the color range with a noticeable yellow tinge are not considered fancy yellow color diamonds.
Factors to Consider When Choosing a Diamond Color
- When a diamond is well cut the diamond’s refraction and dispersion will often disguise certain degrees of color and may make a darker diamond appear whiter when viewed with the unaided eye (without magnification).
- The size of the diamond will also affect the appearance of its color. Color can easily be seen in larger diamonds as opposed to smaller diamonds. Often times it is difficult to see color in diamonds under a 1/2 carat with the unaided eye.
- The shape of the diamond will affect its color as well particularly step cut diamonds such as the Asscher and Emerald that have large open facets and do not display the brilliance of other cuts. The center of these diamonds display a “window effect” where some of the color in the diamond can appear washed out and make it appear whiter then its actual color grade. The shallower the cut of the diamond the more apparent this will be.
Diamond shape is the basic outline of the diamond. Here are some popular shapes sold today.
Round Brilliant is the most popular. It consists of 56 to 58 facets and displays the most brilliance, fire, and scintillation of all diamond cuts on the market today.
Asscher is a stepped square cut also known as the modified square emerald cut. It consists of 72 facets and resembles the shape of an octagon.
Cushion is not as brilliant as many of the more modern cuts, but has a classic romantic look that definitely stands out in a crowd.
Emerald is a cut that provides a very elegant classy look and is known for its long lines. The pavilion is cut with large rectangular facets to create an open effect or optical appearance.
Heart is known as the most romantic of all shaped diamonds. The heart consists of 59 facets and is essentially a pear cut with a cleft at the top.
Marquise resembles the shape of a football when viewed from above. The marquise is bright, clear, and has a great deal of sparkle.
Oval is an adaptation of the round brilliant and usually looks larger than the round brilliant of the same carat weight.
Pear is half oval and half marquise. The pear has 58 facets and displays the brilliance, fire, and sparkle of the round brilliant.
Princess is square shaped with uncut pointed corners. The princess has 58 facets and is known for its brilliance, fire, and sparkle.
A diamond certificate (aka – diamond plot, diamond grading report) is a document certifying a diamond is genuine and is created by a group of gemologists after the diamond is carefully evaluated. The report contains information such as carat weight, color, clarity, proportions, and a cut grade for round diamonds. The certificate also contains a “blueprint” of the diamond’s clarity characteristics.
To understand all aspects of the diamond grading report, click on the GIA link below:
To understand all aspects of the diamond anatomy, click on the GIA link below: