Rock Identifier
Quartz (Silicon Dioxide (SiO2)) — mineral
mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to pale yellowish or smoky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific gravity: approx 2.65.

Hardness
7 on Mohs scale
Color
Colorless to pale yellowish or smoky
Luster
Vitreous (glassy)
Identified More mineral
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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to pale yellowish or smoky; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific gravity: approx 2.65.

Formation & geological history

Forms in a wide variety of environments, primarily through the crystallization of magma or from hydrothermal veins. It is a major constituent of igneous rocks like granite and metamorphic rocks like quartzite.

Uses & applications

Used extensively in glassmaking, electronics (oscillators), abrasives, construction sands, and as a gemstone or collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel knife) and its glass-like conchoidal fracture. Found worldwide; the user's location near 4.9°N, 8.4°E (South-South Nigeria/Cameroon border region) is near various metamorphic and igneous basement complex rocks where quartz veins are very common.