For Seller

By: Ritika Rohilla

Four major components are considered when determining a diamond’s quality and value. They are known as the Four C’s: color, clarity, cut, and carat weight. Understanding these four diamond characteristics and how they interact can help you select a diamond that suits your tastes

Judging Diamond Color

Diamonds are not all truly colorless, but it’s the colorless, often called white, which are diamonds that other shades are judged against. The Gemological Institute of America (GIA) has devised a set of guidelines to grade diamond color. The color of graded diamonds is compared to the color of control stones, reselected gems of a specific color.

Diamond Grading Procedure

1) Graded diamonds must be loose stones, because the color diamonds in settings can be affected by the metal colors used in the mountings.

2) Diamonds are placed table-down, pavilion-up and viewed with a 10X loupe.

3) A lettering system from D to Z is used to identify the amount of color present in each diamond, with D awarded only to rare, totally colorless diamonds.

Other Factors Affect Diamond Color

Fluorescence
GIA diamond reports and many other lab reports indicate whether or not a diamond exhibits fluorescence, which means the diamond’s color changes when it is exposed to ultraviolet radiation. Since UV radiation is a component of daylight and is also present in fluorescent-lit rooms, diamonds with this
characteristic can appear to change color quite often.

1) Diamonds that produce a blue reaction usually appear whiter, or more colorless, under UV light.

2) Stones that fluoresce yellow appear even more yellow under some lighting conditions.

Diamond Color Treatments

The color of some diamonds can be dramatically change by using HPHT (high pressure/high temperature) processing. Unlike diamond colors treatments used in the past, HPHT changes appear to be permanent.

Ritika