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 5, 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

Forms in a wide variety of environments, most commonly in igneous rocks like granite and metamorphic rocks. It crystallizes from magma or precipitates from hydrothermal veins.

Uses & applications

Used extensively in electronics for its piezoelectric properties, glassmaking, timekeeping (quartz watches), jewelry, and as a popular decorative or healing crystal.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is extremely chemically stable and resistant to weathering, which is why it is the primary component of most beach sand.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and conchoidal (shell-like) fracture. Found globally, prominent locations include Brazil, Madagascar, and Arkansas, USA.