sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, colors range from white to gray and yellowish-brown, dull to earthy luster, fine-grained crystal structure, and reacts with dilute hydrochloric acid.
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Physical properties
Hardness of 3 on the Mohs scale, colors range from white to gray and yellowish-brown, dull to earthy luster, fine-grained crystal structure, and reacts with dilute hydrochloric acid.
Formation & geological history
Formed through the accumulation of organic debris like shells, coral, and algal, or through chemical precipitation in shallow marine environments over millions of years.
Uses & applications
Widely used in construction as building material, crushed stone for road bases, and as a primary ingredient in the production of cement and agricultural lime.
Geological facts
Limestone often contains well-preserved fossils and forms dramatic karst topographies featuring caves, sinkholes, and underground rivers.
Field identification & locations
Easily identified by its characteristic reaction to acid fizzing and relatively soft nature, commonly found in sedimentary basins and ancient seabed regions worldwide.
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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
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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