sedimentary

Conglomerate

Clastic sedimentary rock (Conglomerate)

AI-generated identification · may be incorrect

Hardness: 6-7 (based on quartz content); Color: Mottled brown, tan, and grey; Luster: Variable (earthy to waxy depending on clasts); Structure: Clastic with rounded pebbles (>2mm) in a finer matrix; Specific gravity: 2.6-2.8

Hardness: 6-7 (based on quartz content)
Color: Mottled brown, tan, and grey
Luster: Variable (earthy to waxy depending on clasts)

Identified March 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed by the lithification of rounded gravel and pebbles in high-energy environments like riverbeds, alluvial fans, or beaches. Geological age can range from Precambrian to Holocene.

Uses & applications

Used primarily as construction aggregate for concrete, road base, and occasionally as decorative facing stone for buildings or as garden ornaments.

Geological facts

Conglomerate is often nicknamed 'pudding stone' because the rounded pebbles look like fruit in a pudding. It is one of the few rocks that directly records the energy of ancient water systems.

Field identification & locations

Identify by looking for distinct, water-worn rounded stones (clasts) cemented within a finer-grained matrix. Found commonly near ancient or modern river deposits and coastlines.