Accurate Gemelogical Laboratories Inc.

Understanding Appraisals

Diamond Grading

The value of a diamond is determined by a fusion of its characteristics including, Carat weight, Color, Clarity, and Cut.

Carat

Generally, the easiest of the 4 C’s to understand. A diamonds weight is expressed in Carats. One carat is equal to 0.20 grams. Carat is often confused with size, even though it is a measure of weight. Although larger diamonds are generally more expensive, the value of a diamond is judged by a combination of the 4 C’s.

Color

Although many people think diamonds are colorless, these tend to be the most rare. Most diamonds have light shades of yellow or brown. These colors may be caused by the presence of trace elements that entered the diamond while it was still forming. The GIA color grading system for diamonds uses the letters “D” though “Z”, with D being colorless, and Z having the most color within the normal range.

DEF GHIJ KLM NOPQR STUVWXYZ
Colorless Near Colorless Faint Yellow Very Light Yellow Light Yellow

Clarity

Many different types of small crystals or imperfections (sometimes called inclusions in the trade) can be trapped in a diamond while it is formed. The Clarity Grade Scale refers to the number, position and size of an imperfection that occurs naturally inside a diamond and can be seen by magnification of 10x.

FL - IF VVS1 | VVS2 VS1 | VS2 SI1 | SI2; I1 | I2 | I3
Internally Flawless

Internally Flawless
Very Very Slight Inclusions

Internally Flawless
Very Slight Inclusions

Internally Flawless
Slight Inclusions

Internally Flawless
Included

Internally Flawless

Cut

Cut is the only human element added to the diamond. The cut of a diamond is what gives a diamond its brilliance, sparkle, fire and life. If a diamond is poorly cut, the light that enters the diamond from above will leak out through the bottom and sides, and the diamond will not have the optimum amount of brilliance regardless of its other C’s. To Learn more about Cut Grade click here

Shallow Cut:

The diamond looses its brilliance as a result of light lost through the bottom and sides.

Deep Cut:

The diamond appears dark and dull, as light does not reflect through the diamond.

Cut Diagram
Understaning Appraisals