sedimentary
Conglomerate
Conglomerate (clastic sedimentary rock)
Hardness varies by composition (typically Mohs 6-7 due to quartz pebbles), multicolored matrix with rounded clasts, dull luster, clastic texture with visible pebbles/cobbles.
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Physical properties
Hardness varies by composition (typically Mohs 6-7 due to quartz pebbles), multicolored matrix with rounded clasts, dull luster, clastic texture with visible pebbles/cobbles.
Formation & geological history
Formed from the consolidation and cementation of gravel-sized rounded fragments, deposited in high-energy environments like rivers or beaches.
Uses & applications
Used primarily as crushed stone for construction, road aggregate, and occasionally in decorative masonry.
Geological facts
The rounded shape of the clasts indicates that they were transported a significant distance by water or ice, tumbling against each other and wearing down sharp edges before being cemented together.
Field identification & locations
Easily identified by its distinct 'plum-pudding' appearance of rounded pebbles embedded in a finer-grained matrix. Found worldwide in sedimentary basins and ancient riverbeds.
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Arenite (if sandstone)
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Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
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Quartz pebble
Silicon dioxide (SiO2)
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Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
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Sedimentary Sandstone
Arenite (Sedimentary Rock)
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Banded Siltstone / Mudstone Pebble
Siltstone / Argillite
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