Judging quality
Test with a paperclip: true lodestone attracts without help. Octahedral crystals in matrix are the prized specimen form.
Oxide
Magnetite
The most magnetic naturally occurring mineral. Strongly magnetic pieces are called lodestone and will pick up iron filings unaided.
Care
Keep away from electronics and magnetic media. Can rust in damp conditions.
History & lore
Lodestone compasses guided Chinese and later European navigation from roughly the eleventh century.
Cultural history, recorded as tradition rather than as medical or scientific claim.
Common questions about Magnetite
- What is Magnetite?
- The most magnetic naturally occurring mineral. Strongly magnetic pieces are called lodestone and will pick up iron filings unaided.
- How hard is Magnetite and what is it made of?
- Magnetite is a Oxide-family mineral with the composition Fe3O4. It crystallizes in the isometric system and rates 5.5-6.5 on the Mohs hardness scale. It occurs in black.
- Where does Magnetite come from?
- Notable localities for Magnetite include Sweden, USA (Arkansas), Russia, South Africa.
- How do you tell good Magnetite from filler?
- Test with a paperclip: true lodestone attracts without help. Octahedral crystals in matrix are the prized specimen form.
- How do you care for Magnetite?
- Keep away from electronics and magnetic media. Can rust in damp conditions.
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.