mineral

Quartz pebble (Quartztite fragment)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Off-white to light tan. Luster: Vitreous to dull. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Off-white to light tan
Luster: Vitreous to dull

Identified February 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Off-white to light tan. Luster: Vitreous to dull. Crystal structure: Trigonal/Hexagonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Formation & geological history

Formed through the crystallization of magma or precipitation from hydrothermal veins; often rounded by water erosion in sedimentary environments. Common across all geological ages.

Uses & applications

Common quartz is used in construction aggregate, glass making, abrasives, and as a source for silicon in electronics. Common pebbles have negligible industrial value but are foundational to landscape gravel.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. This specific piece shows signs of weathering and mechanical erosion, likely from being part of a concrete mix or riverbed.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. Found globally in riverbeds, soil, and as a component in man-made concrete (as seen in the background).

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