Diamond Grading System

The De Beers "diamond is forever" campaign can be accredited with the immense popularity of this sparkling gemstone. However, the reason why the diamond is romanticized took place eons ago. When the Archduke Maximilian of Hamburg and Mary of Burgundy exchanged diamond rings at their engagement in 1477, little did they know they were starting a tradition that would transcend time, lasting over 5 centuries. With this tradition, the diamond, earlier a symbol of wealth, power and royalty, came to denote a promise of eternal love.

When most people buy diamonds, they pick the stones according to size and sparkle. But we are often presented with a choice between two very similar stones, that have a large disparity in price. The explanation of this lies in the grades. Richard T. Liddicoat proposed and developed the GIA clarity grading system in 1952. Over time, additional research has resulted in changes being incorporated into the system. All good graders adhere to the GIA's diamond grading chart.

The grades illustrate the minute difference in each stone, and thus dictate the value of those highly-priced baubles around your neck, and on your fingers and ears. The method used to evaluate them is called diamond grading, and is based on the diamond grading scales. Each stone is judged based on 4 of its characteristics (called the four C's). Clarity, color and cut (proportion) are the quality elements, which together with the carat weight determine the value of the stone. the diamond grading chart includes

Cut
The cut of the stone determines its sparkle to a large extent. A well-cut diamond is one in which light enters through the crown table and goes to the pavilion, from where it reflects from one side to the other, and then back out of the diamond through the crown table. This ensures maximum sparkle and brilliance. If a diamond is not well cut, the light that enters through the crown gets reflected out through the side or bottom. The GIA Diamond Cut Grading System uses a scale of 5 grades: Excellent, Very Good, Good, Fair and Poor, to ascertain the quality of the diamond. Each grade classifies a number of different proportion sets (angles and percentages) and diamond appearances (shapes).

Clarity
Certain characteristics in the diamond, that mar its clarity are outcomes of events that took place in its formation stages. Called inclusions, they could be bits of crystals of minerals, air bubbles appearing as cloud or feathers, or internal graining. Imperfections that appear on the surface of the diamond that could have taken place during the cutting stage are called blemishes, and also lower the clarity of the stone. The number nature, position, size and color of inclusions and blemishes determine the clarity grade a diamond receives. The clarity of a diamond is graded by using 10X magnification under good lighting by an experienced grader. The GIA diamond clarity grades are mentioned in the table:

Category	Flawless	Internally Flawless	Very Very Slightly Included	Very Slightly Included	Slightly Included	Included
Grade	FL	IF	VVS1 VVS2	VS1 VS2	SI1 SI2	I1 I2 I3

Flawless diamonds have no inclusions under 10 power. Internally flawless ones have small surface blemishes. VVS1 and VVS2 have minute inclusions. VS1 and VS2 have small inclusions. SI1 and SI2 have inclusions that cannot be seen with the naked eye, but are easily visible under 10 power magnification. Inclusions in I1, I2, and I3 are visible to the naked eye.

Color
Contrary to other stones, in a diamond, it is the absence of color that is sought. Stones range from colorless to those with a slightly yellow tinge. They are given grades starting from D and ending at Z. Stones that have a grade beyond Z are sold as colored diamonds. Diamonds with the grade D, E or F are colorless, G to J are near colorless, K, L and M are faint yellow, N to R are very light yellow and lastly S to Z are light yellow. All this is according to the GIA color grading scale.

Carat
Carat is the unit of weight used to measure diamonds. One carat is broken up into 100 points, and equals 1/5 of a gram. For example, a diamond measuring 50 points is ½ carat in weight, or 0.5ct. This unit is used to measure many stones.

The cut and clarity have a profound effect on the brilliance of the diamond. A diamond which has grades closer to the left of any of the scales will be rarer and consequently more highly priced. Understanding the diamond grading system is essential for every buyer. It will equip anyone who chooses to buy a diamond to make an informed and balanced decision.