sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, grayish to tan color, dull to earthy luster, and effervesces strongly in dilute hydrochloric acid.
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Physical properties
Hardness of 3 on the Mohs scale, grayish to tan color, dull to earthy luster, and effervesces strongly in dilute hydrochloric acid.
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 construction as aggregate, for manufacturing cement, in agriculture to neutralize soil acidity, and as a dimension stone.
Geological facts
Limestone frequently contains well-preserved fossils and forms dramatic karst topographies, including underground cave systems with stalactites.
Field identification & locations
Easily identified in the field by its characteristic reaction with acid and soft texture; found globally in sedimentary basins and ancient sea beds.
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Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
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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
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Shale
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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