Smoky quartz

Smoky quartz is a variety of quartz (silicon dioxide) that is colored by admixtures of aluminum, sodium, and lithium. The dark brown to black, almost opaque variety of quartz is called morion, the border between smoky and morion is debatable. Smoky quartz is used in both the goldsmithing industry and the jewelry industry. On the Mohs scale of hardness, it has a hardness of 7. The typical crystal shape is a hexagonal prism with two cusps, in which the prism surfaces are often horizontally grooved. However, twinning or polycrystal growth is common, but we also encounter single crystals

Smoky quartz – a variety of smoky quartz
Smoky quartz is a brown to smoky-colored variety of quartz with the chemical formula SiO₂. It acquires its color due to traces of aluminum and natural irradiation of the crystal structure.

Appearance and properties of tawny quartz
Tawny quartz crystallizes in a hexagonal system and has a hardness of 7 on the Mohs scale. The color ranges from light brown to almost black (so-called morion). Transparent crystals are often cut, while opaque pieces are used as decorative minerals.

Tawny quartz deposits
Significant tawny quartz deposits are found in Switzerland (Alps), Brazil, Russia, Ukraine, the USA and the Czech Republic - for example, in the Highlands.

History and uses of tawny quartz
Tawny quartz was valued in ancient times for the production of decorative objects. Today it is one of the most popular collector's minerals and a raw material for jewelry.