sedimentary
Conglomerate
Clastic Sedimentary Rock
AI-generated identification · may be incorrectHardness varies from 6 to 7 depending on clast composition. Displays rounded to sub-rounded pebbles and gravel cemented in a finer matrix of sand, silt, or clay with dull to earthy luster.
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Physical properties
Hardness varies from 6 to 7 depending on clast composition. Displays rounded to sub-rounded pebbles and gravel cemented in a finer matrix of sand, silt, or clay with dull to earthy luster.
Formation & geological history
Formed in high-energy environments like fast-flowing rivers or beach zones where rounded gravel accumulates and undergoes lithification over millions of years.
Uses & applications
Used primarily in the construction industry as crushed stone for road aggregate and concrete production, and occasionally as decorative facing stone.
Geological facts
Conglomerate is often referred to colloquially as 'puddingstone' due to its textural resemblance to a Christmas pudding filled with embedded pieces of fruit and nuts.
Field identification & locations
Easily identified in the field by its distinct, naturally cemented pebble-sized clasts embedded within a finer-grained matrix. Commonly found in ancient riverbeds and alluvial fans worldwide.
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