sedimentary
Limestone
Calcium carbonate (CaCO3)
AI-generated identification · may be incorrectHardness 3 on the Mohs scale, typically white to gray or tan, dull to earthy luster, and reacts with dilute hydrochloric acid.
Identified More sedimentary →
Explore Limestone in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness 3 on the Mohs scale, typically white to gray or tan, dull to earthy luster, and reacts with dilute hydrochloric acid.
Formation & geological history
Formed through the accumulation of organic remains like shells and coral, or chemical precipitation in marine environments over millions of years.
Uses & applications
Widely used in construction, cement production, agriculture for soil neutralization, and as a chemical feedstock.
Geological facts
Limestone frequently contains well-preserved fossils and forms dramatic landscapes like caves and sinkholes via chemical weathering.
Field identification & locations
Identified easily by its light color, relative softness, and vigorous effervescence when exposed to acid; found globally in shallow marine sedimentary basins.
More like this
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