mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: White to translucent/tan, Luster: Vitreous to waxy (weathered), Crystal Structure: Trigonal/Hexagonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Identified June 16, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to translucent/tan, Luster: Vitreous to waxy (weathered), Crystal Structure: Trigonal/Hexagonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & geological history

Formed from hydrothermal veins or as a primary constituent of igneous and metamorphic rocks. This small pebble has been smoothed and rounded by water erosion in a fluvial or beach environment.

Uses & applications

Used in construction aggregate, glass making, abrasives, and as decorative gravel. High-purity quartz is essential for producing silicon wafers in electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically and physically resistant to weathering, which is why it often remains as pebbles after other minerals have eroded away.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and translucent appearance. These are common in riverbeds, gravel pits, and beaches worldwide.