sedimentary
Belemnite Fossil
Belemnitida (Order within Cephalopoda)
Hardness: 3-4 (Mohs), Color: Brown, grey, or yellowish. Luster: Dull to vitreous when polished. Structure: Bullet-shaped, fibrous calcite structure arranged radially.
- Hardness
- 3-4 (Mohs), Color: Brown, grey, or yellowish
- Color
- Brown, grey, or yellowish
- Luster
- Dull to vitreous when polished
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Physical properties
Hardness: 3-4 (Mohs), Color: Brown, grey, or yellowish. Luster: Dull to vitreous when polished. Structure: Bullet-shaped, fibrous calcite structure arranged radially.
Formation & geological history
Formed from the internal calcified shell (rostrum) of extinct squid-like cephalopods that lived during the Jurassic and Cretaceous periods. Found in marine sedimentary rocks.
Uses & applications
Primarily used for educational purposes, paleontological study, and collector display; sometimes polished for jewelry or amulets.
Geological facts
In folklore, these were often called thunderbolts or thunderstones because they were believed to have fallen from the sky during storms.
Field identification & locations
Look for bullet-shaped or 'cigar-shaped' stony objects in limestone or chalk cliffs. Common in the UK, Germany, and North America.
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