mineral

Quartz (Water-worn pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Translucent orange to tan; Luster: Vitreous to waxy (when polished by water); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Translucent orange to tan
Luster: Vitreous to waxy (when polished by water)

Identified April 13, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids or cooling magma. This particular specimen is a tumble-polished river or beach pebble, shaped and smoothed by mechanical weathering and water erosion over centuries or millennia.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, and as a gemstone for jewelry or decorative landscaping stones.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which has roots in Slavic meaning 'hard'.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and smooth, rounded surface if found in water bodies. It is found globally in almost all geological environments.