8.2" Wide, Natural Smoky Quartz Cluster - Brazil

This is a large smoky quartz crystal cluster from Minas Gerais, Brazil. The crystals are in great condition and the base is flat, allowing for gorgeous, freestanding presentation. This specimen has not undergone any heat treatment of polishing.

The cluster stands 5.7" tall, is 8.2" wide and weighs just under 9 lbs.

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 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.
Quartz var. Smoky
Minas Gerais, Brazil
8.2 x 6 x 5.7"