metamorphic

River Pebble (likely Quartzite or Diorite)

Metamorphosed Quartz-rich Rock / Intermediate Igneous Rock

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs scale), Color: speckled grey and white, Luster: dull/earthy due to weathering, Structure: granular, non-foliated or weakly foliated.

Identified July 8, 2026More metamorphic →

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Physical properties

Hardness: 6-7 (Mohs scale), Color: speckled grey and white, Luster: dull/earthy due to weathering, Structure: granular, non-foliated or weakly foliated.

Formation & geological history

Formed through the metamorphism of sandstone (quartzite) or the cooling of silica-rich magma (diorite). This specimen has been rounded by fluvial erosion in a river or coastal environment.

Uses & applications

Used primarily in landscaping, construction aggregate, and as decorative stone for gardens or fish tanks.

Geological facts

River pebbles are geological travelers; their rounded shape is a record of miles traveled during which sharp edges were ground down by water and other stones.