mineral
Rock Crystal Quartz
Silicon Dioxide (SiO2)
Hardness of 7 on the Mohs scale, clear or transparent color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65
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Physical properties
Hardness of 7 on the Mohs scale, clear or transparent color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65
Formation & geological history
Forms in hydrothermal veins, pegmatites, and as a secondary mineral in various rock types under high pressure and temperature conditions over millions of years
Uses & applications
Used in jewelry, decorative items, optical components, electronics, and crystal healing
Geological facts
Quartz is the second most abundant mineral in Earth's continental crust and exhibits piezoelectric properties, meaning it can generate an electrical charge under mechanical stress
Field identification & locations
Easily identified by its high hardness (scratches glass), clear appearance, and conchoidal fracture; found worldwide with notable deposits in Brazil, Madagascar, and the USA
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Arenite (SiO2 based)
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Limonite / Goethite (Iron Ore Mineral nodule)
FeO(OH)·nH2O / FeO(OH)
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Schist
Schist
Metamorphic
Septarian Pebble
Septarian nodule / Concretion
sedimentary
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral