Smoky Quartz
Quartz var. Smoky Quartz · Semi-Precious Gemstone and Mineral Specimen
Crystal System
Trigonal system, typically presenting as a polished or carved hexagonal prismatic tower with terminal pyramid faces.
Mineral Group
Silicates, specifically Tectosilicates
Chemical Formula
SiO2
Formation Process
Forms primarily through hydrothermal processes, pegmatitic environments, and igneous activity where natural irradiation from surrounding radioactive rocks alters the silicon dioxide lattice.
About This Crystal
A polished hexagonal tower featuring translucent to transparent brown to greyish-brown coloration, vitreous luster on finished surfaces, and internal cloudiness with minor natural fractures and inclusions.
Physical Characteristics
Body color ranges from light grayish-brown to deep blackish-brown; white streak; no true cleavage with a conchoidal fracture; specific gravity around 2.65; brittle tenacity; exhibits piezoelectricity.
Optical Properties
Singly refractive to weak anomalous double refraction; uniaxial positive optical sign; refractive index of 1.544 to 1.553; weak to moderate pleochroism in darker specimens.
Hardness & Durability
Origin Region
Found globally with notable sources in Brazil, Madagascar, the Swiss Alps, and the United States (Colorado).
Hardness & Durability
Mohs hardness of 7; good durability and toughness making it suitable for most types of jewelry, though sharp impacts can cause conchoidal fracturing.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh chemicals and prolonged exposure to direct intense sunlight which can cause the color to fade.
Rarity & Value
Common and widely available; value is determined by size, cut quality, depth of color saturation, and clarity, with prices generally remaining very affordable.
Special Characteristics
Coloration is caused by natural gamma irradiation acting on trace aluminum impurities substituting for silicon within the crystal lattice.
Lore & History
Historically used in ancient Scottish ornamentation and as protective amulets; in modern metaphysical practices, it is traditionally associated with grounding, protection, and the root chakra.