mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous/Glassy, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65
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Physical properties
Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous/Glassy, Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65
Formation & geological history
Forms in igneous, metamorphic, and sedimentary environments through the cooling of silica-rich magma or from hydrothermal veins. It is found in geological formations ranging from billions of years old to relatively recent ones.
Uses & applications
Used in electronics (as piezoelectric crystal), high-end glass manufacturing, jewelry, watch movements, and as a popular metaphysical or decorative specimen.
Geological facts
Quartz is the second most abundant mineral in Earth's continental crust. Rock crystal was once believed to be ice that had frozen so hard it could never melt.
Field identification & locations
Identify by its hardness (scratches glass), lack of cleavage, and transparent clarity. It is commonly found in riverbeds, mountains, and mining sites worldwide, notably in Brazil and Arkansas, USA.
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Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock