sedimentary
Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
AI-generated identification · may be incorrectHardness: 3-4 (Mohs scale), Color: tan, grey, or yellowish brown, Luster: dull/earthy, Crystal structure: microcrystalline matrix with visible fossil casts, Specific Gravity: approx. 2.7
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Physical properties
Hardness: 3-4 (Mohs scale), Color: tan, grey, or yellowish brown, Luster: dull/earthy, Crystal structure: microcrystalline matrix with visible fossil casts, Specific Gravity: approx. 2.7
Formation & geological history
Forms in shallow marine environments where organic debris like shells and coral accumulate and are compacted over millions of years, often dating from the Paleozoic or Mesozoic eras.
Uses & applications
Primarily used in the construction industry as aggregate, for architectural stone, and as a source of lime for agriculture; also valued as educational specimens for fossil collectors.
Geological facts
This particular specimen appears to be a 'clast' containing internal molds or impressions of marine organisms. Many such rocks contain fossil fragments like brachiopods, crinoids, or gastropods.
Field identification & locations
Identify by looking for small holes or distinct shell-shaped impressions on a fine-grained, earthy surface. It will fizz when exposed to weak acid (vinegar). Found globally in areas with ancient seafloor history.
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