Large, 6.9" Smoky Quartz Crystal - Brazil

This is a cluster of large smoky quartz crystals from Brazil. The entire cluster is 6.9 inches wide and the largest crystal is 6.3 inches long. These massive crystals damage free terminations and a beautiful smokey coloration. It has not been heated or treated to change the natural color.

This specimen comes with a stand for display.

Quartz is the name given to silicon dioxide (SiO2) and is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich environments--usually igneous rocks or hydrothermal environments like geothermal waters--at temperatures between 100°C and 450°C, and usually under very high pressure. In either case, crystals will precipitate as temperatures cool, just as ice gradually forms when water freezes. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountain formation: these veins can be hundreds of millions of years old.

Smoky quartz is a grey-brown to black variety of quartz. This common name is derived from the appearance of smoke within the quartz crystal. Depending on the location and the chemicals present during formation, smoky quartz can appear opaque black, but it is typically translucent to some extent. It is believed that the quartz gains this color from a combination of natural irradiation and aluminum impurities.
Quartz var. Smoky
Minas Gerais, Brazil
6.9" long, 5.6" wide. Longest point 7.4"