Mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified March 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of magma or from hydrothermal veins. It can be found in almost all geological ages and environments, particularly in igneous rocks like granite and metamorphic rocks like quartzite.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), optics, construction (as an abrasive), jewelry, and as a popular collector's mineral.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Famous specimens include the 'crystal balls' from ancient Japan and Madagascar. It is known for its ability to generate an electric charge when mechanical pressure is applied.

Field identification & locations

Identify in the field by its hardness (scratches glass), glass-like luster, and lack of cleavage. Commonly found in riverbeds, mountains, and geodes. Tips for collectors: look for well-defined hexagonal prism terminations.