sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on Mohs scale, typically yellowish-brown to white, dull to earthy luster, and reacts strongly with dilute hydrochloric acid.
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Physical properties
Hardness of 3 on Mohs scale, typically yellowish-brown to white, dull to earthy luster, and reacts strongly with dilute hydrochloric acid.
Formation & geological history
Formed by the accumulation of shell, coral, algal, and fecal debris, or through the chemical precipitation of calcium carbonate in marine environments over millions of years.
Uses & applications
Widely used in the construction industry for making cement, as road base, and as a primary agricultural soil conditioner.
Geological facts
Limestone frequently contains well-preserved fossils and forms dramatic landscapes featuring caves and sinkholes due to its solubility in acidic water.
Field identification & locations
Easily identified by its characteristic effervescence when exposed to acid and its soft, fine-grained texture; found globally in marine sedimentary basins.
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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
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Sandstone
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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