mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glass-like)

Identified April 15, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glass-like); 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 occurs in almost all mineral environments and is one of the most common minerals in the Earth's crust.

Uses & applications

Used in electronics (oscillators), manufacturing of glass and ceramics, jewelry making, and highly valued as a decorative collector's specimen.

Geological facts

Quartz is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress. This property makes it essential for keeping time in watches and stabilizing frequencies in radios.

Field identification & locations

Identify by its ability to scratch glass, its lack of cleavage, and its characteristic hexagonal crystal points. It is found globally, notably in Brazil and Arkansas, USA.