sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

AI-generated identification · may be incorrect

Hardness: variable (3-7 Mohs); Color: grey matrix with brown, tan, and orange clasts; Luster: earthy to dull; Structure: clastic texture with rounded rock fragments embedded in a fine-grained matrix; Cleavage: none; SG: 2.5-2.8

Hardness: variable (3-7 Mohs)
Color: grey matrix with brown, tan, and orange clasts
Luster: earthy to dull

Identified May 24, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed in high-energy environments like riverbeds, alluvial fans, or beaches where water currents are strong enough to transport large rounded pebbles. These sediment layers are buried and lithified over millions of years.

Uses & applications

Used primarily in the construction industry as coarse aggregate for concrete and road building. Occasionally used as ornamental stone if the clasts are colorful and well-cemented.

Geological facts

Conglomerates are often referred to as 'puddingstone' in some regions due to their resemblance to a fruit pudding. They are key indicators for geologists to locate ancient river channels.

Field identification & locations

Identify in the field by looking for rounded pebbles or cobbles (clasts) that are cemented within a finer-grained matrix. They are commonly found in regions with sedimentary basin history.