fossil
Fossilized Belemnite Rostrum
Belemnitida
AI-generated identification · may be incorrectHardness: 3-4 (calcite), Color: gray/brown/black, Shape: bullet-like or conical, Composition: mostly calcite
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Physical properties
Hardness: 3-4 (calcite), Color: gray/brown/black, Shape: bullet-like or conical, Composition: mostly calcite
Formation & geological history
Formed from the internal skeleton (rostrum) of extinct squid-like cephalopods, primarily during the Jurassic and Cretaceous periods.
Uses & applications
Collected by fossil enthusiasts; sometimes used in jewelry or as educational specimens.
Geological facts
Belemnites were marine animals related to modern squids and cuttlefish. The part most commonly fossilized is the hard, bullet-shaped rostrum at the tail end of the animal.
Field identification & locations
Identified by its distinctive bullet or cigar shape, often with a radiating crystalline structure in cross-section. Common in marine sedimentary rocks like limestone and shale.
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