Smoky Quartz
Quartz var. Smoky Quartz (Silicon Dioxide) · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal system; typically forming Hexagonal prismatic crystals with pyramidal terminations or massive microcrystalline structures.
Mineral Group
Silicates (Tectosilicate group)
Chemical Formula
SiO2 (with trace Al3+ ions and natural Gamma irradiation)
Formation Process
Igneous and Metamorphic; it forms in pegmatites or hydrothermal veins where free aluminum and natural radiation from surrounding rock act on the quartz structure.
About This Crystal
Transparent to translucent brown-to-grey color ranging from pale tan to nearly black (morion). Displays a vitreous luster with conchoidal (shell-like) fracture patterns.
Physical Characteristics
Color: Smoky brown to black; Streak: White; Cleavage: None/Indistinct; Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: 0.009 (uniaxial positive); Pleochroism: Weak to moderate in brown/yellow-brown tones.
Hardness & Durability
Origin Region
Brazil, Switzerland, Madagascar, and the United States (notably Pikes Peak, Colorado); typically found in pegmatites and metamorphic rocks.
Hardness & Durability
Mohs Hardness: 7; Toughness: Good; Highly durable and stable for daily jewelry wear.
Care & Maintenance
Clean with warm soapy water/soft brush. Avoid extreme heat which can cause color fading. Generally safe in ultrasonic cleaners unless inclusions are present.
Rarity & Value
Common; value is determined by clarity and size. Darker 'Morion' and well-terminated crystals are more valuable for collectors.
Special Characteristics
Often contains rutile inclusions (rutilated) or fluid inclusions (enhydros). Its color is famously induced by natural radiation affecting aluminum impurities.
Lore & History
Historically used in China for some of the first sunglasses in the 12th century. Metaphysically associated with grounding, protection, and the root chakra in traditional lore.