This is a brief overview of diamond grading and provides a base for discussing diamonds. If you have any detailed questions please stop in or email us. While you have probably heard about the famous 4c's, which is covered in this summary, they are just a starting point. The 4c's are a way of quantifying a diamond so that we are able to put it on paper and are able to compare it with another stone. However, one shouldn't base an opinion of a diamond solely on its standing in this scale. There are qualities of diamonds that we are unable to put down on paper and what is gorgeous to one person may not spark anothers' interest. So take a little time in finding your diamond, to ensure that you will enjoy it for the rest of your life.

One of the factors in determining a diamonds value is its color, or lack there of. The Gemological Institute of America's scale of color starts at D, colorless, and continues through the alphabet, getting more of a yellow tint as it goes.

The more colorless a diamond is, the greater its rarity. Therefore, it has a higher value. However, you don't need a D color stone for it to appear colorless. Typically, in a modern round brilliant that is nicely cut, you won't be able to notice any tint if a stone is J color or under and is set with similarly colored diamonds. When color grading diamonds one views the stone from the back side, because it is much easier to see the color, and the color is matched using a master set of stones. The yellow color in diamonds is caused by the presence of nitrogen in the crystal. There are, however, other colors of diamonds not included on this scale. These are referred to as fancy colors. Natural diamond colors can range from intense yellows and browns, to reds, greens, purples, violets, oranges, blues, and pinks. Other than the yellows and browns, these hues are generally not strong or pure, rather they are typically blended or muted with a grayish or brownish tint.

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Clarity refers to the presence of internal features such as breaks or foreign bodies, called inclusions, within a diamond, and to external imperfections such as scratches (these are called blemishes). Both blemishes and especially inclusions lower the clarity grade (and hence the value) of a diamond, but in most cases they have very little effect on a stone's beauty or durability. Inclusions can range from irregularities in the atomic arrangement of a growing crystal, crystals of other minerals, to cleavages or fractures in the stone. The GIA scale for clarity grading begins at FL (flawless) and continues down to I (imperfect).

Imperfect stones contain inclusions that can be seen with the naked eye or that seriously influence durability. Typically the diamonds that we sell are in the SI1 (slightly included) to VS (very slightly included) range. Inclusions in diamonds in these clarity grades do not affect the look or beauty of a stone when viewed with the naked eye.

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A carat is simply a metric unit of weight equal to 1/5 of a gram (a 5 carat diamond would weigh one gram). Diamonds are always bought and sold at a price per carat, the price of course varies depending on the size and quality of the stone. Since larger diamond crystals are more rare, the price per carat increases with greater stone weight. Therefore, a one carat G SI1 will be more expensive than two half carat G SI1 stones. When carat weight is expressed for a 0.50 carat stone, you may hear it as a half carat, point five carats, or a fifty pointer, but they are all interchangeable.

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Cut is the only human factor in the 4c's. Most of what is covered in this summary will only pertain to the round brilliant shape, fancy shapes (such as marquise, oval, emerald, princess, and pear) aren't as brilliant as a round. What you should look for in fancies is brilliance and symmetry, it is much harder to compare them on paper than rounds.

The round brilliant has 58 facets, which produce its brilliance, fire, and scintillation. Even though forms of the round brilliant have been around for hundreds of years, it wasn't until 1919, when Marcel Tolkowsky published the book Diamond Design, that the concept of an ideal cut was formed. To this day, the only changes to his formula are extending the table facet and establishing a girdle thickness. Today there is a big push on Ideal cut stones even though they only make up about 1% of cut diamonds. For many stores it is a way of branding a diamond so customers are able to ask for it by name. Ideal cut stones are beautiful but you will pay a 10-20% premium for them.

GIA has recently released findings of a study they conducted showing that Ideal cuts are not necessarily the brightest stones. The 26-page study, published in the Fall 1998 issue of Gems & Gemology, introduced a new brilliance-tracking calculation called "weighted light return." It concluded that no single set of measurements produces the most brilliant stones and that many combinations of proportions have brilliance the same as or greater than Ideal cuts. GIA president William E. Boyajian even said in a recent interview with Jewelers Circular Keystone, that he "couldn't recommend" the term "Ideal cut" and further called into question whether use of the term "Ideal" was a fair trade practice. "There is no real difference between saying 'Ideal' and saying 'perfect,'" he said. "I question the use of a common descriptive adjective for promotional purposes. By calling a single set of proportions 'Ideal,' you are implying that other well-made stones are inferior. That's not been proven and doesn't seem fair." This information was published in the February 1999 issue of JCK.
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