The way a diamond reacts and glows under ultraviolet light.
A unique quality possessed by some diamonds to give off light when exposed to specific ultraviolet wavelengths. It is an unusual quality that can enhance the appearance of lower color diamonds(J-Z) in certain lighting conditions. However, when fluorescence is very strong the diamond may have an oily appearance that detracts from beauty and value. Only 50% of all gem-quality diamonds fluoresce, and only 10% strongly fluoresce. When gem-quality diamonds fluoresce, it is a bluish color.
When exposed to ultraviolet light, a diamond may exhibit a more white, yellow or blue tint, which may imply that the diamond has a property called Fluorescence. The untrained eye can rarely see the effects of fluorescence. Diamond grading reports state whether a diamond has fluorescent properties. Fluorescence is not considered a grading factor, only a characteristic of that particular diamond.
The naturally-occurring glow emitted by certain diamonds when they are exposed to ultraviolet light. Under most other lighting conditions, it is undetectable to the naked eye. Flourescence may lower the price of some diamonds, but many people actually prefer the effect.
Normally invisible wavelengths of light that become "visible" when exposed to ultraviolet radiation When placed under a lamp which provides ultraviolet light (these lamps provide both "long-wave" and "short-wave" radiation) you will be able to see in pearls a color or colors not seen otherwise A gem or pearl that exhibits color under ultrviolet light Foot