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Candy Triboluminescence

Glow-in-the-dark fun!

By , About.com Guide

Wint-O-Green Lifesavers aren't the only candies that exhibits triboluminescence. Regular sugar cubes will work, as will just about any opaque candy made with sugar (sucrose). Transparent candy or candy made using artificial sweeteners will not work. Most adhesive tapes also emit light when they are ripped away. Amblygonite, calcite, feldspar, fluorite, lepidolite, mica, pectolite, quartz, and sphalerite are all minerals known to exhibit triboluminescence when struck, rubbed, or scratched. Triboluminescence varies widely from one mineral sample to another, such that it might be unobservable. Sphalerite and quartz specimens that are translucent rather than transparent, with small fractures throughout the rock, are the most reliable.

There are several ways to observe triboluminescence at home. If you have wintergreen-flavored Lifesavers handy, get in a very dark room and crush the candy with pliers or a mortar and pestle. Chewing the candy while watching yourself in a mirror will work, but the moisture from saliva will lessen or eliminate the effect. Rubbing two sugar cubes or pieces of quartz or rose quartz in the dark will also work. Scratching quartz with a steel pin may also demonstrate the effect. Also, sticking/unsticking most adhesive tapes will display triboluminescence.

For the most part, triboluminescence is an interesting effect with few practical applications. However, understanding its mechanisms may help explain other types of luminescence, including bioluminescence in bacteria and earthquake lights. Triboluminescent coatings could be used in remote sensing applications to signal mechanical failure. One reference states that research is underway to apply triboluminescent flashes to sense automobile crashes and inflate air bags.

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