mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Mohs hardness 7, colorless and transparent, vitreous (glassy) luster, trigonal crystal system, conchoidal fracture, specific gravity 2.65.
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Physical properties
Mohs hardness 7, colorless and transparent, vitreous (glassy) luster, trigonal crystal system, conchoidal fracture, specific gravity 2.65.
Formation & geological history
Forms in igneous, metamorphic, and sedimentary rocks, especially in hydrothermal veins and pegmatites through cooling silica-rich fluids.
Uses & applications
Used in electronics (piezoelectric oscillators), optics, glassmaking, gemstones, jewelry, and metaphysical collections.
Geological facts
Quartz is one of the most abundant minerals in Earth's continental crust. Ancient Greeks believed clear quartz was ice frozen so hard it would never melt.
Field identification & locations
Can be identified by its hardness (scratches glass, cannot be scratched by a steel knife), glassy luster, lack of cleavage, and transparent glass-like clarity.
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Potassium Feldspar (Orthoclase)
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Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
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