how is light made by rubbing 2 crystal rocks together ?

Question

The crystals are from Calif. @2-3 inches.When rubbed against one another they emmitted light. Was I seeing things or what is the phenomina behind this ?

Answer 1

Light is emitted by atoms when the electrons of the atom become "excited" and jump to a higher energy level. When the electrons return to their more stable ground state they give off the energy in the form of light.

When you rubbed the two rocks together you may have transferred energy to the electrons of some of the atoms. The electrons jumped to a higher level then returned to the ground state giving off the energy in the form of visible light.