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Mineral Magnetism Test Chart

Mineral magnetism is a useful screening property, not an identification verdict. Magnetite commonly gives a strong hand-magnet response, while pyrrhotite can range from weakly to readily magnetic. Hematite or ilmenite specimens may appear weakly magnetic when magnetite is intergrown or attached. A whole rock or sand is a mixture, so one magnetic grain can create a localized response. Use a small enclosed magnet near an intact surface without dragging it, record strong, weak, absent, or localized movement, and repeat the observation. Keep magnets away from implanted medical devices, magnetic storage and cards, compasses, and sensitive instruments; follow magnet and device manufacturer guidance. Magnetic attraction does not confirm a meteorite because terrestrial magnetite-rich rocks and industrial materials are much more common. Bubbles, a red or black streak, industrial context, interior texture, and qualified examination help test that explanation. GeoMiner's private lookup accepts only one of three bounded response categories, records no specimen name, free text, photo, location, magnet strength, or device information, and hands the observation to Quick ID without an account. Combine it with streak, hardness, lustre, cleavage, heft, texture, and geologic context.

Verification resources

Cross-check terminology, classification, methods, and safety with these authoritative external resources.

  • undefined. Strong magnetism as a common magnetite clue, plus weak responses caused by magnetite mixed with hematite or ilmenite.
  • undefined. Pyrrhotite as an iron sulfide sometimes called magnetic pyrite because it is weakly magnetic.
  • undefined. Pyrrhotite magnetic intensity varies with composition.
  • undefined. Why magnetic attraction does not confirm a meteorite and how streak, bubbles, density, and expert examination help.
  • undefined. Using a magnet to separate magnetite grains from a mixed sand sample.
  • undefined. Magnetism as one diagnostic mineral property that should be combined with other observations.
  • undefined. Limits of remote identification and routes to qualified local examination.
  • undefined. Magnetic interference risk for implanted medical devices and the FDA six-inch separation precaution for consumer electronics with high-field-strength magnets.

Read GeoMiner's editorial methodology.

Common questions

Which mineral is strongly magnetic?
Magnetite, including naturally magnetized lodestone, is the familiar strongly magnetic mineral. A strong response supports magnetite but does not prove it because mixtures and manufactured materials may contain magnetic grains.
Does a magnet prove that a rock is a meteorite?
No. Many meteorites attract a magnet, but terrestrial magnetite-rich rocks and industrial materials are much more common. Use bubbles, streak, context, interior texture, and qualified examination.
Why is only one part of my rock magnetic?
A whole rock can contain several minerals. One small magnetite or pyrrhotite grain may create a localized response even when most of the specimen is nonmagnetic.
How can I detect weak magnetism?
Move a small enclosed magnet near the intact specimen without dragging it across the surface. Suspending the magnet from thread may show subtle repeatable deflection.
Is a mineral magnet test safe?
Use a small enclosed magnet and follow its warnings. Keep magnets away from implanted medical devices, magnetic storage and cards, compasses, and sensitive instruments.

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