gemstone
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Hardness: 7 on Mohs scale; Color: Colorless to transparent; Luster: Vitreous; Crystal system: Trigonal/Hexagonal; Cleavage: None; Specific Gravity: 2.65.
- Hardness
- 7 on Mohs scale
- Color
- Colorless to transparent
- Luster
- Vitreous
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Physical properties
Hardness: 7 on Mohs scale; Color: Colorless to transparent; Luster: Vitreous; Crystal system: Trigonal/Hexagonal; Cleavage: None; Specific Gravity: 2.65.
Formation & geological history
Formed in igneous, metamorphic, and sedimentary environments through hydrothermal processes or magma crystallization, typically inside geodes, pegmatites, and veins.
Uses & applications
Used in jewelry, decorative carvings, optical components, electronics (piezoelectric applications), and heavily traded as collector or healing crystals.
Geological facts
Quartz is one of the most abundant minerals on Earth's continental crust. Ancient Greeks believed clear quartz was ice frozen so deeply that it could never melt, leading to the name 'krystallos'.
Field identification & locations
Identified by its transparency, hardness of 7 (scratches glass easily), and conchoidal fracture without distinct cleavage. Found worldwide including Brazil, Madagascar, USA, and the Alps.
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