This Specimen has been sold.
7.4" Tall, Giant Smoky Quartz Crystal Cluster - Brazil
This is a cluster of large smoky quartz crystals from Brazil. The entire cluster is 7.4 inches tall and the longest point is 7.4 inches long. These massive crystals are relatively damage free and have beautiful smokey coloration. It has not been heated or treated to change the natural color.
Silicon Dioxide, also known as SiO2 or Quartz, is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich, hot watery solutions called hydrothermal environments, at temperatures between 100°C and 450°C, and usually under very high pressure. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountains forming, and 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 from the appearance of smoke within the quartz crystal. Dependent on the location and the chemicals present during formation, smoky quartz can appear opaque black, however it’s typically translucent to some extent. It’s believed that the quartz gains this color from a combination of natural irradiation and aluminum impurities.