Materials That Glow

Fluorite

• The word "fluorescence" is derived from the name of this glassy mineral. Fluorescence is the phenomenon that takes place when a substance absorbs light and emits visible light as a longer or shorter light wave even when an external light source has been extinguished. A highly fluorescent mineral, fluorite, is found as a vein deposit mostly with metallic minerals. Low-grade fluorite is used as flux in the production of steel. Intermediate grade fluorite is used in cooking utensils, often as enamel. High-grade fluorite is sometimes used instead of glass in telescopes.

Phosphorus

• A chemical element represented by the symbol "P" on the periodic table, Phosphorus is highly reactive and not found freely on earth. Unlike the glow produced by fluorescence, which is a re-emission of light, the glow produced by phosphorus is caused by a chemical reaction. Phosphorus comes in various forms, but the white and red phosphorus are most common. White phosphorus is highly poisonous and used in bombs and incendiaries. Red phosphorus is more stable and nonpoisonous, and it is used in material such as matches.

Chlorophyll

• The green pigment in plants and algae, chlorophyll, is necessary for photosynthesis. The light absorbed by this chlorophyll becomes energy and is either used to drive photosynthesis, emitted as heat, or emitted as fluorescence. The chlorophyll fluorescence is most often measured by plant physiologists and ecophysiologists to obtain information regarding the efficiency of photosynthesis. The process of photosynthesis is vital for life on earth because it takes carbon dioxide and converts it to organic compounds, releasing oxygen as a waste product.

Miscellaneous

• There are a variety of other materials and organisms that naturally exhibit fluorescence. Jelly fish, for example, have a green fluorescent protein that allows them to glow. This protein has since been developed for use in bioscience to track the development of nerve cells in the brain and watch the process of cancer cells as they spread. It has become a standard laboratory tool. Body fluid, such as semen, urine and blood all contain phosphorus and as a result glow under ultraviolet light. It is common for forensic scientists to use lights to detect the presence of body fluid.