sedimentary

Sedimentary Pebble (Sandstone)

Clastic Sedimentary Rock (SiO2 dominant)

AI-generated identification · may be incorrect

Hardness: Approx. 6-7 (Mohs scale), Color: Grayish-green with reddish-brown hematite staining, Luster: Dull/Earthy, Crystal Structure: Microcrystalline with visible clasts, Specific Gravity: 2.3-2.6

Hardness: Approx

Identified June 27, 2026More sedimentary →

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Physical properties

Hardness: Approx. 6-7 (Mohs scale), Color: Grayish-green with reddish-brown hematite staining, Luster: Dull/Earthy, Crystal Structure: Microcrystalline with visible clasts, Specific Gravity: 2.3-2.6

Formation & geological history

Formed through the accumulation and cementation of mineral particles or rock fragments (clasts). The rounded shape indicates significant water transport in a river or coastal environment, likely from the Holocene or Pleistocene era.

Uses & applications

Common river stones are used for decorative landscaping, gravel production, and as aggregate in construction and concrete.

Geological facts

The reddish-brown spots are likely 'Liesegang rings' or hematite inclusions caused by iron-rich water seeping through the porous stone and oxidizing over time.

Field identification & locations

Identify in the field by its rounded, water-worn edges and granular texture. Commonly found in riverbeds, glacial tills, and beaches. For collectors, look for unique mineral patterns like these iron stains.