Clear Quartz (Rock Crystal)
Quartz (Alpha Quartz) · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal; Habit is typically hexagonal prisms terminated by six-sided pyramids; also occurs in massive, druzy, and microcrystalline forms.
Mineral Group
Silicates (Tectosilicates)
Chemical Formula
SiO2
Formation Process
Primarily Hydrothermal (crystallizing from silica-rich hot water in veins and cavities) or Igneous (magmatic crystallization in pegmatites).
About This Crystal
Colorless to white, transparent to translucent with a vitreous (glassy) luster. The specimen shows a crystalline, slightly sugary druzy texture with small reflective crystal faces and occasional dark mineral inclusions.
Physical Characteristics
Color: Colorless/White; Streak: White; Cleavage: None (poor/indistinct); Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Usually none; Piezoelectric properties present.
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: 0.009 (Uniaxial positive); No pleochroism; Low dispersion (0.013).
Hardness & Durability
Origin Region
Found globally; notable sources include Brazil (Minas Gerais), Madagascar, Arkansas (USA), and the Alps.
Hardness & Durability
Mohs Hardness: 7; Toughness: Good (no cleavage); High stability against most chemicals except hydrofluoric acid; very durable for jewelry.
Care & Maintenance
Safe to clean with warm soapy water, ultrasonic cleaners, and steam. Store away from harder stones like Topaz or Sapphire to avoid scratches.
Rarity & Value
Very Common; Value is determined by clarity, size, and unique inclusions. Massive or druzy white quartz is inexpensive and widely available.
Special Characteristics
Piezoelectricity (creates electrical charge under pressure); can contain phantom inclusions of other minerals or enhydros (fluid inclusions).
Lore & History
Historically used for hardstone carving since antiquity. Known as the 'Master Healer' in metaphysical traditions, associated with the Crown Chakra and believed to amplify energy.