Diamond Fluorescence: The Finer Factor of a Great Diamond

A diamond's fluorescence cannot be identified using the naked eye. The fact is, only about one-third of the world's diamonds possess fluorescence. The most recommended method to detect a diamond's fluorescence is to use an ultraviolet lamp. A diamond that has fluorescence emits a soft-colored glow when exposed to ultraviolet light.

In a nutshell, a diamond that possesses a strong fluorescence may enhance the appearance of a colorless-grade stone by making it look whiter (or more colorless) when viewed under natural light conditions. Conversely, a very strong fluorescence may contribute a milky and oily appearance on a regular diamond, which negatively affects the market price of that particular stone.

The diamond fluorescence grading scale runs from faint to medium to very strong. Stones that possess little or slight glow under ultraviolet light are rated as faint while those that emit a clear and deep glow are rated as very strong. Diamond fluorescence also varies in color with blue being the most common. Other hues include yellow, green, and white.