mineral

Quartz (Water-worn Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Translucent grey to white; Luster: Vitreous to waxy (when worn); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture).

Hardness: 7 on Mohs scale
Color: Translucent grey to white
Luster: Vitreous to waxy (when worn)

Identified July 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Translucent grey to white; Luster: Vitreous to waxy (when worn); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture).

Formation & geological history

Formed from silica-rich hydrothermal fluids or within igneous and metamorphic rocks. This specific specimen has been rounded and smoothed by water erosion in a river or beach environment.

Uses & applications

Quartz is used in glassmaking, electronics (piezoelectric properties), abrasives, and as a gemstone or decorative stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'quarz', which had its origin in Slavic languages.

Field identification & locations

Identify by its hardness (can scratch glass) and lack of cleavage. Common in riverbeds, beaches, and gravel pits worldwide. Collectors look for clarity and internal inclusions.