sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, typically buff, gray, or tan in color, with a dull to earthy luster and fine-grained crystal structure.
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Physical properties
Hardness of 3 on the Mohs scale, typically buff, gray, or tan in color, with a dull to earthy luster and fine-grained crystal structure.
Formation & geological history
Formed through the accumulation and compaction of organic remains like shells and coral, or chemical precipitation in marine environments over millions of years.
Uses & applications
Widely used in the construction industry as crushed stone for road base, aggregate in concrete, and for the production of cement and agricultural lime.
Geological facts
Limestone frequently contains well-preserved fossils of ancient marine organisms and dissolves easily in weakly acidic groundwater to form spectacular cave systems.
Field identification & locations
Easily identified by its characteristic effervescence when a drop of dilute hydrochloric acid is applied; commonly found in sedimentary basins worldwide.
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Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
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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