Fractoluminescence

Fractoluminescence is the emission of light from the fracture of a crystal. Depending upon the atomic and molecular composition of the crystal, when the crystal fractures a charge separation can occur making one side of the fractured crystal positively charged and the other side negatively charged. If the charge separation results in a large enough electric potential, a discharge across the gap and through the bath gas between the interfaces can occur. The potential at which this occurs depends upon the dielectric properties of the bath gas. Fractoluminescence is a subset of the more broad category of mechanoluminescence which is light emission resulting from any mechanical action on a solid. Also, fractoluminescence is often mistaken for triboluminescence which, strictly speaking, is light emission caused by the rubbing together of two surfaces, resulting from charge build-up on the surfaces.

See also

• Mechanoluminescence
• Triboluminescence