sedimentary
Conglomerate
Clastic Sedimentary Rock
AI-generated identification · may be incorrectHardness varies (generally 6-7 for quartz pebbles), multicolored due to diverse clasts, dull to earthy luster, fragmental crystal structure, variable specific gravity around 2.6-2.7.
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Physical properties
Hardness varies (generally 6-7 for quartz pebbles), multicolored due to diverse clasts, dull to earthy luster, fragmental crystal structure, variable specific gravity around 2.6-2.7.
Formation & geological history
Formed by the consolidation and cementation of gravel-sized rounded clasts, such as pebbles and boulders, typically deposited in high-energy environments like fast-flowing rivers or beaches.
Uses & applications
Used primarily as crushed stone for construction, road aggregate, and occasionally as decorative facing stone or dimension stone.
Geological facts
Conglomerates are often referred to as 'puddingstone' when the matrix contrasts sharply in color with the rounded pebbles. They provide direct evidence of ancient high-energy water currents.
Field identification & locations
Easily identified in the field by its distinct rounded gravel clasts embedded within a finer-grained sand or mud matrix. Common worldwide wherever ancient riverbeds or coastal deposits outcrop.
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Fossiliferous Sedimentary Rock
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fossil
Sandstone or Siltstone
Arenite (if sandstone)
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Sandstone
Arenite
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Shale
Shale (clastic sedimentary rock)
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Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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