Clear Quartz
Quartz var. Rock Crystal · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal; typically hexongal prisms with pyramidal terminations; this specimen is a tumbled/massaged habit
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 (Silicon Dioxide)
Formation Process
Primary crystallization from hydrothermal veins, pegmatites, and magmatic environments over a wide range of temperatures
About This Crystal
A tumbled, translucent to transparent colorless stone with a vitreous luster. It features internal fractures or veils and a subtle yellowish-iron staining inclusion or internal crackle
Physical Characteristics
Color: Colorless/Transparent; Streak: White; Cleavage: None/Indistinct; Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Usually inert
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: 0.009 (Low); Optical Character: Uniaxial positive; Dispersion: 0.013
Hardness & Durability
Origin Region
Global distributions; major commercial sources include Brazil, Madagascar, and Arkansas (USA)
Hardness & Durability
Mohs Hardness: 7; Toughness: Good; Stability: Highly stable against most acids and heat, though rapid thermal shock can cause cracking
Care & Maintenance
Safe to clean with warm soapy water, ultrasonic cleaners, and steam. Avoid hydrofluoric acid. Store separately to prevent scratching softer stones
Rarity & Value
Abundant/Common; Value is generally low for tumbled stones, determined by clarity and size. Treatments like irradiation or dyeing are common for other quartz varieties
Special Characteristics
Features internal 'veils' or 'feathers' (liquid/gas inclusions) and a visible yellow iron oxide stain or inclusion line within the crystal structure
Lore & History
Historically used for lenses and carvings; known as 'frozen ice' by ancient Greeks. In lore, it is considered a 'Master Healer' associated with the Crown Chakra and clarity