sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, colors range from white to gray and tan, dull to earthy luster, and exhibits a strong reaction to dilute hydrochloric acid.
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Physical properties
Hardness of 3 on the Mohs scale, colors range from white to gray and tan, dull to earthy luster, and exhibits a strong reaction to dilute hydrochloric acid.
Formation & geological history
Formed through the accumulation of organic remains like shells and coral or chemical precipitation in shallow marine environments over millions of years.
Uses & applications
Widely used in construction as crushed stone for road base, a primary component in manufacturing cement, and in agricultural soil treatment.
Geological facts
Limestone frequently contains well-preserved fossils and forms dramatic landscapes such as caves and sinkholes via chemical weathering.
Field identification & locations
Identify in the field by its characteristic softness and effervescence when tested with acid; found globally in sedimentary basins and ancient sea beds.
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Other sedimentary specimens
Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image
fossil
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary