Triboluminescence is light emitted by the mechanical stimulation of crystals. The first people to use it might have been a Native American tribe. Learn about the physics of glowing crystals and the people who used it.
You can generate triboluminescence relatively cheaply. All it takes is some quartz, which most of you can pick up around your homes. You'll find it either in the dirt, or in people's driveways. If nowhere else you can find them in the rock bins at educational stores and online. Take the edge of one crystal and rub it against another. You can also rub the surfaces together, or even bang them together. You should see flashes of orange light.
It's tough to say exactly why you see those flashes, though. Scientists believe that, as the crystals in the quartz are broken apart, the charges in them are separated. As charge can flow, that separation is temporary. In its haste to get back, the charge collides with molecules in the air, exciting their electrons enough to make them give off light.
It seems that perhaps the first people to harness this power for their own amusement were the Ute people of Colorado and Utah. Making use of the natural quartz in the area, they created rattles with outer skins so thin that the quartz inside would flash when the rattles were waved in the dark.
Image: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0