mineral

Quartz (Gravel)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Transparent to milky white; Luster: Vitreous/glassy; Crystal Structure: Trigonal/hexagonal; Cleavage: None/conchoidal fracture; Specific gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: Transparent to milky white
Luster: Vitreous/glassy

Identified May 29, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Transparent to milky white; Luster: Vitreous/glassy; Crystal Structure: Trigonal/hexagonal; Cleavage: None/conchoidal fracture; Specific gravity: 2.65.

Formation & geological history

Formed through cooling of magma or precipitation from hydrothermal veins. These specific specimens are alluvial or glacial gravel, meaning they have been weathered and transported by water or ice.

Uses & applications

Used in concrete and asphalt, making glass, electronics (oscillators), abrasives, and as semi-precious gemstones in jewelry.

Geological facts

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

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife and its glass-like appearance. It is found globally in almost all geological environments.