History records the use of crystals as both functional and ornamental.
The gods of ancient myth wore them in their breastplates. Priests of many societies and brotherhoods often wore bejeweled amulets and plates, which acted as oracles and voice pieces from which advice was obtained.
The Atlanteans used crystals for healing, communication, weather control, and record keepers. The Tibetans used them to produce light.
Mayans used crystals in their statues. In Peru, Spanish chronicles recorded that when they invaded the Incan Empire and captured the King, the Queen and the priests immediately fled to the Temple of the Sun in Cuzco, where they communicated with other regents of the land, and decided what was to be done, by gazing into the black mirror situated at the Temple’s center.
Resources:
WWW.ED.GOV
WWW.CRYSTALCAVERN.COM
WWW.CRYSTALSHOP.COM