mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified July 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments including igneous, metamorphic, and sedimentary settings. It typically crystallizes from magma or precipitates from hydrothermal veins. It is found in rocks of all geological ages.

Uses & applications

Extensively used in electronics for its piezoelectric properties, in glass making, as an abrasive, and widely used in jewelry, carvings, and as a collector's specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz is also known as 'rock crystal'. Ancient Greeks believed it was ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its ability to scratch glass (hardness 7), hexagonal crystal habit, and shell-like (conchoidal) fracture. It is found globally, with significant deposits in Brazil, Arkansas (USA), and Madagascar.