What is Crystal?
A Crystal is a uniform body with a geometric lattice. The varying structures of the lattice are the causes of the varying physical properties of the Crystals and therefore also of the minerals and gems.
Piezoelectricity is that quality by which electricity and sometimes light is produced by compression. Many cultures and spiritual traditions have used Crystals in Ritual, often striking them to produce flashes of visible light.
Piezoelectricity is that quality of an electrified state or polarity which is produced by variation in temperature. Quartz has both piezoelectric and piezoelectric properties which mean that the polarity of Quartz Crystal will change when subject to pressure or heat as well as when held.