mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, most commonly by crystallizing from cooling magma or precipitating from hydrothermal veins. It is a major component of igneous rocks like granite and metamorphic rocks like quartzite.

Uses & applications

Used extensively in electronics for its piezoelectric properties (watches, clocks, radios), in glassmaking, as an abrasive, and frequently in jewelry and crystal healing markets.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as Rock Crystal, a term derived from the Greek word 'krustallos' meaning ice, as ancient Greeks believed it was permanently frozen water.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and hexagonal crystal habit (six-sided prisms with pyramidal ends). It is found globally in almost all geological environments.