Smokey Quartz is light brown to black, sometimes smokey grey. The colouring is caused by gamma radiation, either naturally imparted to the stone or artificially so.
Quartz, the second most abundant mineral in the earth's continental crust after Feldspar, derives its name from the Slavic word for "hard". It has been a prized gemstone for thousands of years being attractive, hard (7.0 on the Moh's scale), as well as inexpensive.
An abundance of material means there is little requirement to purchase anything other than eye-clean pieces.
