sedimentary
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
Hardness: 3-4 (Mohs scale), Color: Gray to tan with white inclusions, Luster: Dull to earthy, Structure: Clastic/Biogenic, Cleavage: None (conchoidal fracture), Specific Gravity: 2.5-2.7
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Physical properties
Hardness: 3-4 (Mohs scale), Color: Gray to tan with white inclusions, Luster: Dull to earthy, Structure: Clastic/Biogenic, Cleavage: None (conchoidal fracture), Specific Gravity: 2.5-2.7
Formation & geological history
Formed in marine environments where organic debris, such as shells and coral, accumulates and is compacted over millions of years. This specimen likely dates from the Paleozoic or Mesozoic eras.
Uses & applications
Used in construction as a building material, in the manufacturing of cement, as a decorative garden stone, and as a popular educational specimen for fossil collecting.
Geological facts
Limestone covers about 10% of the total surface of the Earth's land. Fossiliferous limestone is special because it acts as a biological archive of ancient marine life.
Field identification & locations
Identify by looking for visible shell fragments or fossils embedded in a fine-grained matrix. It will react and 'fizz' (effervesce) when exposed to a drop of diluted hydrochloric acid or strong vinegar. Found commonly in areas with ancient seabeds.
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