The GIA created the now globally accepted standard for describing a diamond’s, Color, Cut, Clarity and Carat Weight, known as the 4Cs of diamonds. The creation of the 4Cs allows diamond quality to be communicated in a universal language so customers know exactly what they’re about to purchase. As the creators of the diamond 4Cs and the International Diamond Grading System, GIA is the global authority and the world’s trusted source of unbiased assessment.
Actually, the evaluation of white diamonds is based on the absence of color. A chemically pure, colorless or near colorless diamond has little to no hue of color and thus a higher value. The GIA’s D-to-Z color-grading system measures the degree of colorlessness by comparing a stone under controlled lighting and precise viewing conditions to master stones of established color value. Many of the color distinctions are so subtle that they are invisible to the untrained eye. These subtle distinctions in grading can make a big difference in price.
A diamond’s clarity refers to the quantity and placement of inclusions and blemishes. A diamond is the result of carbon exposed to tremendous heat and pressure deep in the earth. This process can result in a variety of internal characteristics called “inclusions” and external characteristics called “blemishes”. Evaluating diamond clarity involves determining the number, size, relief, nature and position of these characteristics and how they affect the overall appearance of the stone.
Diamonds are renowned for their ability to transmit light and sparkle. How a diamond is cut and polished directly affects the amount of sparkle and brilliance that comes off the stone when it interacts with light. Precise artistry and workmanship are required to fashion a stone so its proportions, symmetry and polish deliver that one-of-a kind return of light.
Carat weight is the measurement of how much a diamond weighs. A carat can be subdivided into 100 points. This provides a precise measurement to the hundredth decimal place. For example, a 0.75 carat can be referred to as a ‘seventy-five pointer’ or a ‘three quarter carat’. This precision system was created because even a small difference in carat weight can affect the overall value and price of the diamond.