sedimentary
Conglomerate
Clastic Sedimentary (Conglomerate)
Hardness: Variable based on clasts (often 6-7 if quartz-rich), Color: Brown, tan, and gray, Luster: Dull/Earthy matrix with waxy clasts, Texture: Coarse-grained with rounded clasts over 2mm
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Physical properties
Hardness: Variable based on clasts (often 6-7 if quartz-rich), Color: Brown, tan, and gray, Luster: Dull/Earthy matrix with waxy clasts, Texture: Coarse-grained with rounded clasts over 2mm
Formation & geological history
Formed by the lithification of rounded gravel and pebbles in high-energy environments like riverbeds, alluvial fans, or beaches where water movement rounds the stones.
Uses & applications
Used as decorative stone, construction aggregate, concrete filler, and historically as a building material for walls and foundations.
Geological facts
Conglomerates are often referred to as 'puddingstone' due to their resemblance to plum pudding. They are key indicators of past water flow and high-energy geological environments.
Field identification & locations
Identify by looking for rounded pebbles (clasts) cemented together in a finer-grained matrix. Commonly found near ancient river systems and shorelines.
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