Clear Quartz (Rock Crystal)
Quartz var. Rock Crystal · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal; typically prismatic with pyramidal terminations, though this specimen shows a massive/shattered habit.
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2
Formation Process
Primarily hydrothermal, occurring in veins where silica-rich fluids cool and crystallize in rock cavities.
About This Crystal
Colorless and transparent to translucent with a vitreous (glassy) luster. The specimen exhibits conchoidal fracture patterns and internal veiling.
Physical Characteristics
Color: Colorless; Streak: White; Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: +0.009; Doubly refractive; Uniaxial positive.
Hardness & Durability
Origin Region
Brazil, Madagascar, USA (Arkansas), and the Alps are major global sources.
Hardness & Durability
Mohs Hardness: 7; Extremely durable and resistant to scratching from most household materials; no cleavage.
Care & Maintenance
Safe to clean with warm soapy water, ultrasonic cleaners, and steam; store away from harder gems like Topaz or Sapphire.
Rarity & Value
Common; value is determined by clarity and size. Massive specimens are inexpensive, while water-clear crystals command higher prices.
Special Characteristics
Displays piezoelectric and pyroelectric properties; this specimen contains internal reflections and fractures (veils).
Lore & History
Historically known as 'Krystallos' (frozen ice) by Greeks; culturally regarded as a 'master healer' in traditional metaphysical beliefs.