5.4" Smoky Quartz Cluster - Brazil

This is an unusual cluster of dark black, smoky quartz crystals from Brazil. The entire plate is 5.4 inches wide and the longest point is just over 2.6 inches long. The crystals on the specimen a strange pitting to them, possibly indicating incomplete formation. It has not been heated or treated to alter the dark, natural color.

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.
SOLD
DETAILS
SPECIES
Quartz var. Smoky
LOCATION
Brazil
SIZE
5.4"long, 3.6" wide, Largest point 2.6"
CATEGORY
SUB CATEGORY
ITEM
#69534