Judging quality
A genuine rostrum has radial fibres visible on any broken end and a small conical socket at the wide end. Perfect uniform 'bullets' with no socket are usually reshaped fragments.
Fossil
Belemnite
The bullet-shaped internal skeleton of an extinct squid relative. Cut and polished, the calcite shows a radiating fibrous structure from a central apical line.
Care
Calcite: acid-sensitive and soft. Dry storage.
History & lore
English country tradition called them thunderbolts or Devil's fingers, said to have fallen during storms.
Cultural history, recorded as tradition rather than as medical or scientific claim.
Common questions about Belemnite
- What is Belemnite?
- The bullet-shaped internal skeleton of an extinct squid relative. Cut and polished, the calcite shows a radiating fibrous structure from a central apical line.
- How hard is Belemnite and what is it made of?
- Belemnite is a Fossil-family mineral with the composition CaCO3 (calcite rostrum). It crystallizes in the trigonal system and rates 3-4 on the Mohs hardness scale. It occurs in brown, amber, grey.
- Where does Belemnite come from?
- Notable localities for Belemnite include England (Jurassic coast), Germany, Russia, Morocco.
- How do you tell good Belemnite from filler?
- A genuine rostrum has radial fibres visible on any broken end and a small conical socket at the wide end. Perfect uniform 'bullets' with no socket are usually reshaped fragments.
- How do you care for Belemnite?
- Calcite: acid-sensitive and soft. Dry storage.
Related stones
See it in person
Photographs only go so far
Both rooms are open six days a week, and there is always someone happy to pull pieces out of the case so you can compare them under the light.