sedimentary
Fossiliferous Limestone
Fossiliferous Calcilutite / Biomicrite
Hardness: 3-4 (Mohs scale), Color: Dirty gray to tan with brown fossil inclusions, Luster: Dull or earthy, Texture: Fine-grained matrix containing visible fossil fragments.
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Physical properties
Hardness: 3-4 (Mohs scale), Color: Dirty gray to tan with brown fossil inclusions, Luster: Dull or earthy, Texture: Fine-grained matrix containing visible fossil fragments.
Formation & geological history
Formed in warm, shallow marine environments through the accumulation of calcium carbonate and the skeletal remains of marine organisms. This specimen likely contains fragments of crinoids or small shells from the Paleozoic or Mesozoic eras.
Uses & applications
Primarily used for geological education, lime production, construction aggregate, and as decorative stone in architecture.
Geological facts
Fossiliferous limestone often acts as a natural record of prehistoric oceans; many specimens can date back hundreds of millions of years and map changes in sea levels.
Field identification & locations
Identify by a dull finish that fizzes when exposed to weak acid (dilute HCl) and the presence of small, imprinted biological patterns. Commonly found in riverbeds or coastal cliffs where ancient seabed layers are exposed.
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