Herkimer diamond (SiO2) is the generic name for double-terminated quartz crystals, first discovered in dolostone outcrops in Herkimer County, New York. They became largely recognized after workmen discovered them in large quantities while cutting into the Mohawk River Valley dolostone in the late 1700s. These quartz crystals which formed very slowly in small solution cavities have 18 facets and two terminations. Some may even form enhydros, quartz crystals with pockets of water within the crystal.
The popularity of mining for double terminated quartz crystals in Herkimer County is what led to the name Herkimer diamonds.
Metaphysically Known For: Dreams, visions, purification, spiritualization of physical life.