sedimentary
Limestone
Calcareous sedimentary rock (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, typically white, gray, or buff in color with a dull to earthy luster. Composed primarily of the mineral calcite and often contains fossil fragments.
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Physical properties
Hardness of 3 on the Mohs scale, typically white, gray, or buff in color with a dull to earthy luster. Composed primarily of the mineral calcite and often contains fossil fragments.
Formation & geological history
Formed through the accumulation and compaction of organic debris like shell, coral, and algal remains in shallow marine environments over millions of years.
Uses & applications
Widely used in the construction industry for crushed stone, cement production, and as a dimensional building stone.
Geological facts
Limestone dissolves slowly in weak acid, which forms extensive cave systems and underground drainage networks known as karst topography.
Field identification & locations
Easily identified in the field by its characteristic fizz when a drop of dilute hydrochloric acid is applied due to carbon dioxide release.
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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