The Four C’s Overview | Determining Diamond Quality and Diamond Size

Determining Diamond Quality and Size

Use the grading of these 4 C’s ONLY as a guide and not a base to make your entire purchase off of. There are different variables at play even within the same color, or clarity, grades that can make one diamond appear much more beautiful than another. We always recommend working one on one with a

CARAT

Carat is not a measure of a diamond’s size but, rather a measure of a diamond’s weight. One carat can also be divided into 100 points. A 0.75 carat diamond is the same as 75 points or 3/4 carat diamond. The most important thing to remember when it comes to a diamond’s carat weight is that it is not the only factor that determines a diamond’s value. To determine a diamond’s actual size, we also look carefully at its spread or measurements. This is measured in millimeters and tells how large or small the diamond appears face up in relation to its weight.

COLOR

Refers to the degree to which a diamond is colorless. The closer a diamond is to colorless, the rarer and more valuable it is. Diamonds are graded on a color scale established by the Gemological Institute of America (GIA). Grades D, E, and F make up the colorless range which are very valuable. The Near Colorless Range of G, H, I, and J is very popular and offers a lot of value. Color differences can be very subtle and grading is done under measured lighting and compared against a “master diamond” for accuracy. This color chart is representative of the color grades of a diamond. *Note that this chart does not apply to fancy color diamonds such as yellow, pink, and blue which have their own system for grading. For diamond shapes like round brilliant, emerald, asscher, radiant, cushion we would recommend a J color or above. For elongated diamond shapes such as pear and oval, I color and above is a good option. Do note this also fluctuates based on the diamond and your color sensitivity.

CLARITY

Refers to the presence of inclusions in a diamond. Inclusions are natural identifying characteristics such as minerals or fractures, that appear while the diamonds are being formed. They may look like tiny crystals, pinpoints, clouds or feathers. Inclusions are ranked on a scale of perfection known as the clarity scale. The scale ranges from F (Flawless) to I (Included) and is based on the visibility of inclusions at 10x magnification. In determining a clarity grade, the GIA system considers the size, nature, position, color, and number of clarity characteristics visible under 10x magnification. Some inclusions have little effect on the attractiveness of a diamond. Inclusions such as an excess of clouds could impact the dispersion of light making the diamond less brilliant.

As a standard we would not recommend diamonds within the included clarity range since the imperfections would be visible to the naked eye. Clarity affects each diamond’s cut and shape differently so it is important to go on a case-by-case basis.

For Brilliant cut diamonds we would typically recommend at least an SI2 or above depending on the exact diamond.

CUT

The cut of a diamond refers to the exact proportions, quality of polish and the arrangement of a diamond’s facets. A diamond has facets that allow light to enter it, become refracted, and exit in a rainbow of colors. As illustrated below, when a diamond is cut to ideal proportions, light will then reflect from one facet to another and disperse through the top of the stone, resulting in a display of brilliance and fire. Diamonds that are cut too deep or too shallow lose light, resulting in less brilliance, fire, scintillation, and value.

Keep in mind that GIA only provides a concrete cut grade for round brilliant cut diamonds. All other shapes will not receive a cut grade however we can ascertain the cut by its proportions. When it comes to fancy shape diamonds, we will know more about its shape based on its length to width ratio. Without seeing the diamond physically, it can tell you what to expect from its overall outline.

In our loose stone video gallery we feature tons of loose diamonds with quality comparisons.