mineral
Quartz
Silicon Dioxide (SiO2)
Hardness of 7 on the Mohs scale. Color ranges from colorless and white to yellow, milky, or smoky. It exhibits a vitreous to greasy luster, hexagonal crystal system, and has no true cleavage, instead breaking with a conchoidal fracture. Specific gravity is approximately 2.65.
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Physical properties
Hardness of 7 on the Mohs scale. Color ranges from colorless and white to yellow, milky, or smoky. It exhibits a vitreous to greasy luster, hexagonal crystal system, and has no true cleavage, instead breaking with a conchoidal fracture. Specific gravity is approximately 2.65.
Formation & geological history
Quartz forms in a wide variety of geological environments. It is a major component of igneous rocks like granite, metamorphic rocks like quartzite, and sedimentary rocks like sandstone. It often crystallizes from silica-rich hydrothermal veins.
Uses & applications
Widely used in electronics (oscillators, quartz clocks), glassmaking, abrasives, gemstone carvings, and jewelry.
Geological facts
Quartz is the second most abundant mineral in Earth's continental crust, surpassed only by feldspar. Its piezoelectric properties make it essential for modern timekeeping and electronics.
Field identification & locations
Can be identified easily in the field by its hardness (scratches glass), lack of cleavage, and characteristic conchoidal fracture. Found globally in almost all rock types.
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Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
sedimentary
Limonite / Goethite (Iron Ore Mineral nodule)
FeO(OH)·nH2O / FeO(OH)
mineral
Septarian Pebble
Septarian nodule / Concretion
sedimentary
Schist
Schist
Metamorphic
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral