sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness 3 on the Mohs scale. Colors range from white, gray, to tan. It has a dull to sub-crystalline luster and reacts strongly with hydrochloric acid.
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Physical properties
Hardness 3 on the Mohs scale. Colors range from white, gray, to tan. It has a dull to sub-crystalline luster and reacts strongly with hydrochloric acid.
Formation & geological history
Formed through the accumulation of shell, coral, algal, and fecal debris, often in shallow marine environments over millions of years.
Uses & applications
Widely used in construction as a building material, aggregate in road base, and in the production of cement and agriculture lime.
Geological facts
Limestone frequently contains fossils of marine organisms and forms spectacular cave systems through dissolution by acidic groundwater.
Field identification & locations
Easily identified by its characteristic effervescence when exposed to acid and its soft, fine-grained texture. Found globally in 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
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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