sedimentary
Conglomerate
Conglomerate (clastic sedimentary rock)
Clastic texture with rounded to sub-rounded fragments (clasts) larger than 2mm, matrix-supported, various colors depending on clast composition, dull luster, Mohs hardness varies (3-7) based on mineral content.
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Physical properties
Clastic texture with rounded to sub-rounded fragments (clasts) larger than 2mm, matrix-supported, various colors depending on clast composition, dull luster, Mohs hardness varies (3-7) based on mineral content.
Formation & geological history
Formed by the lithification of rounded gravel and pebbles in high-energy environments such as riverbeds, alluvial fans, or mountain shorelines.
Uses & applications
Used in the construction industry as coarse aggregate for concrete and road building; sometimes used as architectural stone or for landscaping.
Geological facts
Conglomerates are often referred to as 'pudding stones' due to their appearance of rounded pebbles embedded in a finer matrix, resembling raisins in a pudding.
Field identification & locations
Check for rounded, water-worn pebbles cemented together by a finer-grained matrix like sand or silt. Commonly found in ancient river channels and sedimentary basins.
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