The 4 C’s: The factors that determine a diamonds quality
The carat weight, color grade, clarity grade, and cut will determine diamond quality, but there’s no “right answer” to how a diamond should look. Many people in the market for an engagement ring will prioritize one factor in favor of another.
Carat: The unit of measurement used to describe a diamonds weight
Diamonds are weighed in metric carats: one carat is equal to 0.2 grams, about the same weight as a paperclip. (Be careful not to confuse “Carat” with “Karat”, as in “14k gold”, which refers to gold purity)
Just as a dollar is divided into 100 pennies, a carat is divided into 100 points. For example, a 50-point diamond weighs 0.50 carats. However, 2 diamonds of equal weight can have very different values depending on the other members of the Four C’s.
The carat weight of the diamond is often the most visually apparent factor when comparing diamonds
Color: Diamond color actually means the lack of color
Diamond color evaluation of most diamonds is based on their absence of color
The universalized GIA color grading scale is D-Z, with D being the “whitest/ having no hue or tint”
G-H-I-J: Near Colorless
K-L-M: Faint yellow
N-O-P-Q-R: Very light yellow
S-T-U-V-W-X-Y-Z: Light yellow
Typically, many of the diamond color distinctions are so subtle that they are invisible to the untrained eye.
The color of a diamond can be more visible in certain shapes like oval, pear and marquise, while some shapes like round and emerald will actually “hide” their color.
What color diamond is right for you? That depends on your personal preference and your eye’s ability to distinguish the subtle differences.
Please keep in mind, your choice of metal, may impact the overall color appearance of your diamond. For example, a yellow gold ring may lessen the ability to notice the differences in color between 2 diamonds.
Clarity: The absence of inclusions and blemishes
What are inclusions and blemishes? Inclusions are internal characteristics and blemishes are external characteristics.
What causes inclusions? Small crystals can become trapped in a diamond when it’s forming. Sometimes as the crystal grows, it can develop irregularities in its atomic structure. The size, position and visibility of inclusions can have a significant impact on a diamond’s clarity.
Diamond clarity involves determining the number, size, relief, nature and position of these characteristics, as well as how they affect overall appearance of the stone.
The GIA diamond clarity scale has 6 categories, some of which are divided, for a total of 11 specific clarities.
Flawless (FL) No inclusions or blemishes visible under 10x magnification
Internally Flawless (IF)No inclusions visible under 10x magnification
Very, Very Slightly Included (VVS1 and VVS2) Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
Very Slightly Included (VS1 and VS2) Inclusions are observed with effort under 10x magnification, but can be characterized as minor
Slightly Included (SI1 and SI2)Inclusions are noticeable under 10x magnification. Depending on the shape of the diamond and the type of the inclusion, they may be able to be seen with the naked eye.
Included (I1, I2 and I3)Inclusions are obvious under 10x magnification and can typically be seen with the naked eye. This may affect the brilliance of the diamond causing a hazy and foggy appearance.
Cut: Not just the shape.
Most individuals believe the “Cut” of the diamond is the shape. Although choosing the right shape of diamond for your hand, lifestyle and personal preference is important, the “Cut” of diamond means something entirely different.
Diamond cut is how well the diamonds facets interact with light.
GIA only grades the cut of round diamonds. All other cut grades are the opinion of the cutters and/or gemologist based on the specific proportions. They also take into account the design and craftsmanship of the diamond, its weight relative to its diameter, its girdle thickness, the symmetry of the facet arrangement and the quality of polish on those facets.
All of these factors will determine how successfully the diamond interacts with the light to create the desirable visual effects, such as:
Brightness: Internal and external white light reflected from a diamond
Fire: The scattering of white light into all the colors of the rainbow
Scintillation: The amount of sparkle a diamond produces, and the pattern light and dark areas caused by reflections within the diamond