mixed

River Pebbles and Quartz

Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)

AI-generated identification · may be incorrect

Hardness: 6-7 on Mohs scale; Color: variety of whites, browns, grays, and pinks; Luster: vitreous to dull/earthy; Crystal Structure: mainly cryptocrystalline or coarse-grained; Cleavage: none/conchoidal.

Hardness: 6-7 on Mohs scale
Color: variety of whites, browns, grays, and pinks
Luster: vitreous to dull/earthy

Identified April 21, 2026More mixed →

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Physical properties

Formation & geological history

Formed through various geological processes including cooling of magma (granite), metamorphism (quartzite), and mechanical erosion in riverbeds or coastal environments over millions of years.

Uses & applications

Used in landscaping, decorative aquariums, craft jewelry, construction aggregates, and as starter pieces for rock tumbling and amateur collections.

Geological facts

River pebbles become smooth through a process called saltation, where they are bounced along a riverbed, grinding against other rocks to remove sharp edges.

Field identification & locations

Identify in the field by looking for rounded, smooth surfaces near water sources or glacial deposits. Common in all geographical regions with fluvial history.