Education: Diamonds

Understanding Diamond Grading

You’ve heard it before…Diamonds are a girl’s best friend. However, they’re not just for girls anymore. Today, diamonds are the gem of choice for women and men.

Getting the best diamond for your money requires a bit of knowledge. Before purchasing diamonds it’s best to understand how jewelers appraise and price them. There are four main criteria established by the Gemological Institute of America (GIA) that help determine a diamond's quality and value. You’ve heard of the 4Cs:cut, color, clarity and carats. Jewelers use these ratings to determine a diamond's value. It’s important for you to understand the 4Cs to help you determine the true value of your diamond purchase.

There are various grading systems in place to define the color, cut and clarity of a diamond. The two most common systems in use in this country are the Gemological Institute of America (GIA) and the American Gem Society (AGS) systems.

Diamond grading is a skill acquired through years of experience, often combined with formal education available through industry organizations. In America the Gemological Institute of America and the American Gem Society are two respected institutions providing education in diamond grading as well as other jewelry skills.

Both the GIA and the AGS have laboratories that produce grading reports for diamonds. The GIA report provides a color and clarity grade, a diagram of physical charcateristics and the measurements of the diamond. Reports produced by the AGS assign a cut grade as well. The GIA has refrained from providing a cut grade on their reports because there is no agreement on the best way to cut a diamond.

The two systems differ in terminology but most experienced jewelers will do a reasonable job of translating one system to another. It's always best to deal with an expert. One who holds diplomas from the GIA or AGS training programs.

Color

Color grading diamonds is one of the most challenging tasks a Gemologists faces. Diamonds are found in nature in every color. The variance in color is one of the factors that make it more difficult to determine the amount of color present in a diamond. Color grading machines are relatively new to the industry. They help sort diamonds into color groups for final grading by an expert. The expert assigns the final grade by comparing the diamond to a set of color masters.

Women, generally, see color better than men. On our buying trips Caroline grades the diamonds for color while I do the clarity grading.

When shopping for a diamond be sure the diamond has a grading report. Most people can see clarity characteristics through a microscope but color is difficult to remember. If all the diamonds in a particular display case are of a lower color it will not be apparent until your diamond is compared to one of higher color. At Van Scoy Jewelers we provide a Grading Report by the Gemological Institute of America or one produced by a Gemologist on our staff. Either way you have a record of the grade in writing.

Remember that some day your diamond will be compared to another. That's the day you'll be glad you chose Van Scoy Jewelers.

Cut

The term Cut in this context refers to the faceted proportions to which the diamond is finished. The optical beauty of the finished diamond, the way it disperses and reflects light, is determined in large part by its final dimensional properties. A well-cut diamond has more sparkle and brilliance than a poorly-cut diamond. You should always consider Cut first when looking for sparkle and brilliance. Cut is a description of quality while shape describes the face-up profile, or outline of the diamond.

Today we have machines to help up with the tedious process of measuring and calculating the Cut grade of a diamond. In seconds, the computer measures every facet and calculates a final Cut grade. The latest in Cut grading technology is pictured here. There is no agreement on the exact or ideal proportions a diamond should be cut to, but there is a clear consensus that Cut is important and a diamond needs to fall within certain parameters. The final decision regarding the Cut of the diamond you purchase is yours but as always, it's best to consult an expert. Choose a local jeweler you trust and ask them to explain the importance of Cut.

Our cutter is based in Antwerp Belgium. Antwerp is one of four major cutting centers in the world and is known to be the center where the majority of the world’s higher quality polished diamonds are produced. It is a truly beautiful city, a business center, as well as an historic seaport.

Clarity

Most diamonds have physical characteristics, very tiny natural marks within the stone. The size and quantity of inclusions directly impact the amount of light that passes through the diamond. Every grade of diamond, from Flawless to SI1 (slightly included), appears exactly the same to the naked eye. Hence, clarity grading, like color grading, is a skill that requires experience and education. Here at Van Scoy Jewelers we use the Gemological Institute of America Grading scale. Many of our diamonds are supplied with reports produced by the GIA.

The diamond grader's primary tool for clarity grading is the microscope. The GIA grading system is based on observation at 10-power magnification. Clarity grading is the translation of the visual impact of inclusions and other regularities contained within or on the surface of the diamond into a clarity grade. The clarity characteristics are evaluated on five factors. The factors are size, nature, position, number and relief.

Carat Weight

The weight of a diamond is expressed in carats. A carat is equal to one fifth of a gram. There are 155 carats to the troy ounce. The diameter of a well-cut one carat round diamond is about 6.50 mm or .25 inches. We determine the weight of a diamond by weighing it on an extremely accurate scale.