mineral

Quartz (Water-worn Pebble)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Translucent tan to milky white; Luster: Vitreous/Glassy; Structure: Hexagonal crystal system (though rounded by erosion); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent tan to milky white
Luster: Vitreous/Glassy

Identified March 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed from cooling magma or hydrothermal veins. This specific specimen became a rounded pebble through mechanical weathering and transport in a river or beach environment over thousands of years.

Uses & applications

Used widely in glass making, abrasive manufacturing, and electronics (due to piezoelectric properties). Pebbles like this are often used in landscaping, aquarium decor, or as pocket stones for beginners.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krustallos', meaning ice, as ancient Greeks believed it was ice frozen so hard it would never melt.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. It is commonly found in gravel pits, riverbeds, and beaches worldwide. To collectors, these represent the durability of silica-based minerals.

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