Dendritic Quartz Points
Please note that crystals and stones are natural products and are rarely perfect.
It gets its name from a Greek word meaning tree-like, and this is quite descriptive of these stones. They are usually colorless, white or gray, with tree-like or fern-like inclusions of iron or manganese. The inclusions are called dendrites.
Quartz crystal exhibits the property of piezoelectricity, by which it can transform mechanical energy (e.g., pressure) into electromagnetic energy, and vice versa. This makes it useful in such as devices crystal radios, microphones, watches, radio transmitters, etc. Clear Quartz is sometimes called ‘Rock Crystal,’ and is the stone most often thought of when the term ‘Quartz’ is used. The name comes from the Greek for ‘ice,’ and some of the ancients believed that Quartz crystal was water frozen so hard it could never thaw.
Source: The Book of Stones pg.387