sedimentary

Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: white to light gray, translucent; Luster: waxy to vitreous; Crystal structure: Trigonal (though rounded by water); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: white to light gray, translucent
Luster: waxy to vitreous

Identified July 10, 2026More sedimentary →

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Physical properties

Hardness: 7 on Mohs scale; Color: white to light gray, translucent; Luster: waxy to vitreous; Crystal structure: Trigonal (though rounded by water); Specific gravity: 2.65

Formation & geological history

Formed via crystallization from silica-rich fluids (hydrothermal or igneous) and later eroded into a stream or beach pebble through water action, likely during the Holocene or Pleistocene era.

Uses & applications

Used in construction aggregates, landscaping, and occasionally as a source of silica for glassmaking or in jewelry lapidary for tumbling.

Geological facts

Quartz is one of the most abundant minerals on Earth's crust. Most beach and river pebbles in temperate zones are composed of quartz because of its extreme physical and chemical durability compared to other minerals.

Field identification & locations

Identify by its inability to be scratched by steel, its smooth water-worn surface, and its resistance to acid. Commonly found in riverbeds, glacial deposits, and along coastlines.