sedimentary

Belemnoit (Fossil)

Belemnoidea (Order), Rostrum / Guard

AI-generated identification · may be incorrect

Hardness: 3 (made of calcite); Color: Tannish-grey, brown, or white; Luster: Dull to earthy (weathered); Structure: Bullet-shaped or cigar-shaped with a radial crystalline structure internally.

Hardness: 3 (made of calcite)
Color: Tannish-grey, brown, or white
Luster: Dull to earthy (weathered)

Identified April 20, 2026More sedimentary →

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Physical properties

Hardness: 3 (made of calcite); Color: Tannish-grey, brown, or white; Luster: Dull to earthy (weathered); Structure: Bullet-shaped or cigar-shaped with a radial crystalline structure internally.

Formation & geological history

Belemnites were cephalopods that lived during the Devonian to the end of the Cretaceous period. This specimen is the 'rostrum,' the hard internal shell part that fossilized in marine sedimentary environments.

Uses & applications

Primarily used for educational purposes, scientific study of paleo-climates, and as collector specimens in the fossil trade.

Geological facts

Folklore often called these 'Thunderbolts,' believing they fell from the sky during storms. They are related to modern-day squid and cuttlefish but had a hard internal counterweight.

Field identification & locations

Identify by the distinctive 'bullet' shape and circular cross-section. Found globally in coastal areas and quarries containing Mesozoic era sedimentary rock layers.