mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glass-like)

Identified March 11, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in a variety of geological environments, most commonly from the cooling of silica-rich magma/hydrothermal veins or through metamorphic processes. It is one of the most abundant minerals in the Earth's crust.

Uses & applications

Used widely in electronics (oscillators), optics, glass manufacturing, abrasives, jewelry, and as decorative metaphysical specimens.

Geological facts

Quartz is piezo-electric, meaning it generates an electric charge when mechanical pressure is applied. This property makes it essential for timekeeping in watches and clocks.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and vertical striations on crystal faces. This specific specimen has been carved and polished into a 'tower' or 'obelisk' shape. Common worldwide, with major deposits in Brazil and Arkansas, USA.