Diamond Education
The 4Cs
The most important aspect of a diamond is the cut. The right cut can make even a lower color or clarity diamond sparkle like a star. Although there is a lot of science behind a diamond, there is also the matter of taste and individual perception of what makes a diamond beautiful. While not everyone will share the same opinion as to what constitutes beauty, most people do want a diamond that expresses their individual taste and personality. We are your local jewelry experts in helping you find the best quality diamond at the best possible price.
Here’s information on how to choose the best diamond and what you should consider before making a purchase: Diamond Cut, Diamond Color, Diamond Clarity, and Carat Weight. These are known as the 4Cs of diamond grading. To see a full explanation of each of the 4Cs, click on the characteristic you wish to learn more about:
Diamond Color Grade
The Experts at Work
It’s truly fascinating to see our skilled diamond graders at work analyzing a diamond’s color.
Using a master set of diamonds specifically chosen based on their range of color, the graders pick up the diamond they are grading with tweezers and place it next to the individual diamonds in the master set. The diamond grader then makes a skilled judgment call — something that requires good eyes and extensive experience.
Unmounted Diamonds Provide a More Accurate Grade
Diamonds not in a setting and, therefore, loose are called unmounted. That’s how we grade ALL our diamonds. We do this so that the color is not influenced by the metal of the setting. For example, a diamond set in a yellow-gold ring could appear more yellowish in tone than one in a white-metal mounting. By grading loose diamonds, we get the best and most accurate read possible.
An Easy to Understand Scale
Most labs grade based on a scale using D as the best color, down to Z. This way, you will have a better understanding of its color.
Clarity
Like the Cut grade, the laboratory reports come with alphanumeric and verbal descriptors for Clarity. Again, the international standards are used.
The verbal descriptors are trade terms originally developed to describe diamonds for diamond manufacturers and retailers. Over time, these terms have become recognized at the consumer level as well, and because they are widely accepted, we adhere to them, too.
The Grades are from highest to lowest in Clarity quality as follows:
- Flawless/Internally Flawless (F/IF) — Very rare for diamonds!
- Very, Very Slightly Included (VVS1 and VVS2) — Also very rare.
- Very Slightly Included (VS1 and VS2)
- Slightly Included (SI1 and SI2)
- Included (I1 , I2, and I3)
Cut
A Cut Grade Like No Other
You’ve probably heard that the most important factor of the 4Cs is Cut. We present this information to you based on the easy-to-understand numeric and verbal descriptors.
Easy-to-Understand Grades
The grades in diamond grading reports for a diamond’s cut are based on proprietary numeric and verbal descriptors. The numeric descriptors for the diamond Cut Grade follow the international standards for how well a diamond is cut. When reviewing the cut qualifications, it’s pretty easy to see which is best — no guessing what it all means!
Carat Weight
The carat is the unit of measurement for the physical weight of diamonds. One carat equals 0.200 grams or 1/5 gram and is subdivided into 100 points. For comparison, in units more familiar in the United States, one carat equals 0.007 ounce avoirdupois.
Carat Weight is the most objective of the diamond’s 4Cs. It involves no estimates, comparisons, or judgments. All that is required is a precisely balanced scale capable of measuring extremely small weights. Carat Weight is measured using a digital scale. Despite the ease of measurement and the relative unimportance of diamond weight, there are some facts you should understand about a diamond’s weight and price.
Comparing the value of diamonds by Carat Weight is like comparing the value of paintings by size. A wall-sized canvas by an unskilled artist may be bigger than a miniature by Rembrandt, but it will not be worth more. Large diamonds are rarer than smaller ones, and as the carat weight increases, the value of the diamond increases as well. However, the increase in value is not proportionate to the size increase.
For example, a one-carat diamond will cost more than twice that of a ½-carat diamond (assuming Color, Clarity, and Cut grade are the same). Weight does not always enhance the value of a diamond, either. Two diamonds of equal weight may be unequal in value, depending upon other determining factors such as Cut, Color, and Clarity. In fact, if a diamond is improperly cut, the added weight may serve only to reduce its brilliance.
For these reasons you should consult us regarding the weight, quality, and value of a particular diamond. The best way to see the difference in weight versus cut is to look at a national grading laboratory’s “perfectly cut” diamond and compare it to the others. You will see a noticeable difference.
Diamond Terms
Baguette shape
A rectangular-shaped diamond with rows of step-like facets. If the baguette’s two long sides taper inward, it is called a Tapered baguette.
Bar setting
Similar to the channel setting, it is a circular band of diamonds that holds each stone in by a long thin bar, shared between two stones.
Barion cut
This has a traditional step-cut crown and a modified brilliant-cut pavilion. A square barion cut diamond has 61 facets, excluding the culet.
Bearding or girdle fringes
The outermost portion of the diamond, called the girdle, can develop small cracks that resemble whiskers during the polishing process. The bearding can sometimes be removed, if not too dramatic, with slight re-polishing, and if the weight allows.
Bezel setting
With a bezel setting, a rim holds the stone and completely surrounds the gem. Bezels can have straight edges, scalloped edges, or can be molded into any shape to accommodate the stone.
Blemishes
The term blemish is used when the diamond has scratches or marks on the external area of the stone.
Brilliance
Liveliness, or sparkle in a stone when light is reflected from the surface and from the total internal reflection of light.
Brilliant-cut
Brilliant cuts are scientifically found to reflect the most light from within the stone, and often are considered to have the most brilliance of all cuts. A round brilliant-cut diamond has 58 facets. Other brilliant cuts include the heart, oval, marquise and pear shaped.
Carat
Refers to the measure of weight of a diamond. One carat is equivalent to 200 milligrams. One carat can also be divided into 100 “points.” A .75-carat diamond is the same as a 75-point or 3/4-carat diamond.
Certification (or Diamond Grading Reports)
There are many recognized gemological laboratories that can grade your diamond for a fee.
Channel setting
Used most frequently for wedding bands and anniversary bands, a channel setting will set the stones right next to each other without metal separating them.
Clarity
A diamond often has natural imperfections, commonly referred to as “nature’s fingerprints.” These inclusions contribute to a diamond’s identifying characteristics. Inclusions are found within the diamond. Inclusions can be white, black, colorless, or even red or green. Most inclusions are undetectable by the human eye, and can only be seen with 10X magnification. Inclusions are ranked on a scale of perfection called clarity. The grades of clarity vary from F (Flawless) and IF (Internally Flawless) through to I (Included). Clarity scale I (Included) can be seen by the human eye without magnification. The position of these birthmarks can affect the value of the diamond.
Cluster setting
This setting surrounds a larger center stone with several smaller stones. It is designed to create a beautiful larger ring from many smaller stones.
Color
Diamonds are graded on a color scale established by the Gemological Institute of America (GIA). The scale ranges from D (colorless) to Z. Fancy colors refer to diamonds with hues like pink, blue, green, yellow and very rarely red. Fancy colors are not included in this color scale and are considered extremely rare.
Crown
This is the upper portion or the top of a diamond.
Culet
The bottom point of the diamond. It may be polished in some stones. Please note that sometimes the cutter may choose to make the culet a surface instead of a point.
Cushion cut
A mixed-cut diamond shaped like a square pillow.
Cut
Cut refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a polished diamond. Based on scientific formulas, a well-cut diamond will internally reflect light from one mirror-like facet to another and disperse and reflect it through the top of the stone. This results in a display of brilliance and fire. Diamonds that are cut too deep or too shallow lose or leak light through the side or bottom, resulting in less brilliance and ultimately value.
Cutting style
Cutting styles are different than diamond shapes. The simplest and most common way to explain cutting style is to categorize it into the following three basic types: Step-cut, Brilliant-cut and Mixed-cut.
Deep cut
Cut refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a finished diamond. When a diamond is cut too deep, it will lose or leak light through the side or bottom. This results in less brilliance and value.
Diamond
A diamond is the hardest known natural substance. It is crystallized carbon. Diamonds are mined in rough form and then cut and polished to reveal their brilliance.
Diamond Grading Reports
There are many recognized gemological laboratories that can grade your diamond for a fee.
Dispersion
When light enters a diamond it reflects off the facets and the angles cut into the stone. This distribution of light is known as dispersion, or the display of the spectral colors.
Emerald shape
A rectangular or square-shaped cut-cornered diamond.
Facets
These are tiny surfaces polished onto a rough diamond that give a finished diamond its shape. The way light interacts with these facets affects a diamond’s brilliance and sparkle.
Fancy shapes
Any diamond shape other than round – e.g. marquise, square, emerald, oval, heart and pear.
Feather
A feather is a type of inclusion or flaw within a diamond. It is described often as a small crack, fissure or gletz.
Finish
The word finish is used to describe the exterior of the diamond. If a diamond is well polished, it has a very good finish.
Fire
Often a term used instead of “dispersion,” it is the variety and intensity of rainbow colors seen when light is reflected from a diamond.
Flat-top setting
Like the Gypsy setting, this setting has a band that is one continuous piece that gets thicker at the top. A flat-top setting grows broader at the top so that a faceted stone can be inserted into the ring at the broadest part. The stone is held in place by metal chips attached at the stone’s girdle.
Fluorescence
When exposed to ultraviolet light, a diamond may exhibit a more whitish, yellowish or bluish tint, which may imply that the diamond has a property called fluorescence. The untrained eye can rarely see the effects of fluorescence. Diamond grading reports often state whether a diamond has fluorescent properties. Fluorescence is not considered a grading factor, only a characteristic of that particular diamond.
Girdle
The girdle is the outermost edge of the diamond between the crown and the pavilion.
Growth or grain lines
These can be considered internal flaws, and can often be seen only by rotating the diamond very slowly. They can appear and disappear almost instantaneously. They appear as small lines or planes within the diamond.
Gypsy setting
The Gypsy setting is predominantly used for men’s jewelry. The band is one continuous piece that gets thicker at the top. The top is dome shaped and the stone is inserted in the middle.
Illusion setting
This setting is more intricate than others in that it surrounds the stone to make it appear larger. The metal that surrounds the stone usually has an interesting design.
Inclusions
Often referred to as “nature’s fingerprints,” these are internal imperfections within most diamonds. They are what make a diamond so unique, as a fingerprint does for a person. These birthmarks are measured on a scale of perfection known as clarity. Some common names of inclusions include cloud, crystal, pinpoint, and feather. The position of inclusions can affect the clarity of a diamond and therefore the value.
Marquise shape
A boat-shaped diamond that is long and thin with gently curved sides that come to a point on either end. Marquise is part of the brilliant-cut family.
Mixed-cut
This cut has both step-cut and brilliant-cut facets. Mixed cuts combine the beauty of the emerald cut with the sparkle of the brilliant cut.
Pavilion
Bottom portion of the stone, under the girdle, measuring to the culet.
Pinpoint
A pinpoint is a small dot, which is an inclusion within a diamond. A gathering of pinpoints is called a “cluster” or “cloud.” A cloud or cluster can appear as a hazy area in the diamond.
Polish
Indicates the care taken by the cutter in shaping and faceting the rough stone into a finished and polished diamond.
Princess cut
A square or sometimes rectangular-shaped modified brilliant-cut diamond.
Prong or claw setting
It consists of four or six claws that cradle the diamond. Because this setting allows the maximum amount of light to enter a stone from all angles, it sometimes can make a diamond appear larger and more brilliant than its actual weight. This setting can also hold larger diamonds more securely.
Proportion
The proportions of a diamond are very important, so that the maximum amount of light be reflected off and out of a stone. Proportion is the relationship between the angles of the facets of the crown and pavilion.
Radiant cut
A rectangular or square shaped diamond with step-cut and scissor-cut on the crown and a brilliant-cut on the pavilion.
Scintillation
When light reflects from a diamond, the sparkling flashes that come from the facets of the gem are known as scintillation.
Shallow cut
Cut refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a finished diamond. When a diamond is cut too shallow, it will lose or leak light through the side or bottom. This results in less brilliance and value.
Shape
Shape refers to form or appearance of a diamond – i.e. whether the diamond is round, triangular, square, marquise, pear, oval or heart-shaped.
Step-cut
The step cut has rows of facets that resemble the steps of a staircase. The emerald cut and the baguette are examples of the step cut.
Symmetry
A diamond’s symmetry is the arrangement of the facets and finished angles, created by the diamond cutter. Excellent symmetry of a well-cut and well-proportioned diamond can have a great effect on the diamond’s brilliance and fire. Grading reports will often state the diamond’s symmetry in terms Excellent, Very good, Good, Fair, or Poor.
Table facet
This is the largest facet of a diamond. It is located on the top of the diamond. The table facet is sometimes referred to as the “face.”
Table spread
Term used to describe the width of the table facet, often expressed as a percentage of the total width of the stone.
Tension setting
Term used to describe the width of the table facet, often expressed as a percentage of the total width of the stone.
Tolkowsky, Marcel
In 1919 Marcel Tolkowsky calculated the best theoretical compromise for the cut of a diamond to release the most beauty. The width of the table facet was found to be 53% of the total width of the stone, with a pavilion angle of 40 degrees and 45 degrees. The Tolkowsky cut provides the basis for the modern American cut.
Trillion shape
Is a triangular-shaped diamond with 50 facets. Trillions are commonly used as side stones.
Well cut
Well cut proportions ensure the maximum compromise between fire and brilliance. When light enters a properly cut diamond, it is reflected from facet to facet, and then back up through the top, exhibiting maximum brilliance, fire and sparkle.
The information on this site was aggregated from the education section of the Gemological Institute of America’s website (https://www.gia.edu/) and the American Gemological Society website: https://agslab.com/education-diamond-color-grade.php#