sedimentary

Conglomerate

Sedimentary Clastic Rock

AI-generated identification · may be incorrect

Hardness varies by clast composition (Mohs 6-7 typically); color is multicolored or variable depending on source rocks; dull luster; clastic texture with rounded gravel and pebble fragments cemented by a finer matrix.

Identified November 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed by the consolidation and cementation of rounded gravel-sized and boulder-sized clasts in high-energy environments like fast-flowing rivers or beaches.

Uses & applications

Used primarily as crushed stone for road construction and aggregate in concrete, as well as decorative facing stone.

Geological facts

Conglomerates are often referred to as 'puddingstones' when the matrix contrasts sharply with the rounded pebbles. They provide direct evidence of ancient high-energy water currents.

Field identification & locations

Identified easily by its characteristic rounded gravel clasts embedded in a finer sand or mud matrix. Found worldwide in ancient river channels and coastal deposits.