sedimentary

Conglomerate

Clastic sedimentary rock (Polymictic Conglomerate)

AI-generated identification · may be incorrect

Hardness: Variable (based on parent rocks); Color: Multi-colored clasts in a reddish-brown or sandy matrix; Luster: Dull/Earthy; Structure: Clastic with rounded grains >2mm; Specific Gravity: Approx 2.6-2.9

Hardness: Variable (based on parent rocks)
Color: Multi-colored clasts in a reddish-brown or sandy matrix
Luster: Dull/Earthy

Identified March 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the lithification of rounded gravel and boulders. Rounded shapes indicate transport by high-energy water (rivers or beaches). Found in ancient riverbeds and alluvial fans throughout geological time.

Uses & applications

Commonly used as a coarse aggregate in the construction industry for roads and concrete. Occasional use as ornamental stone or for building facings.

Geological facts

Conglomerate is often called 'puddingstone' because it looks like raisins in a pudding. Similar rocks with sharp, angular fragments are called breccia instead of conglomerate.

Field identification & locations

Identify in the field by looking for large, rounded clasts (stones) cemented together by a finer-grained matrix. Found in sedimentary basins and mountain ranges globally.