1.4" Double-Terminated Smoky Quartz Crystal - Tibet
This is a natural smoky quartz crystal from the Himalayan Mountains of Tibet. This type of smoky quartz is commonly referred to as "Double-Terminated Tibetan Smoky Quartz". It earns its name for its terminations at each end. Some crystals from this location have black inclusions, while others have smoky coloration due to natural irradiation. These crystals will often have enhydro (water bubbles) inclusions which are best found using good lighting and rotating the crystal, watching for any bubble or inclusion movement within the crystal.
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.
Silicon Dioxide, also know 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.