What is Magnetism Test? A magnetism test checks whether a mineral is attracted to a magnet and how strongly it responds. This is a fast way to flag magnetite and to screen heavy sands for magnetic concentrate. Keep the magnet covered so filings don’t build up and contaminate other samples. Record the strength of the response along with streak and luster to make the result useful later.
With a Magnetism Test, test both attraction and distance—strongly magnetic material may jump to the magnet, while weak response may require contact. Keep the magnet in a bag or wrap it with tape so it stays clean and doesn’t shed iron grains onto specimens. Write “strong,” “weak,” or “none,” and note if cleaning the surface changes the response. Magnetism is most informative when you log it alongside streak, luster, and hardness.
Magnetism Test vs. “it’s black so it’s magnetic” Many black minerals are not magnetic. Use a magnet instead of color as the deciding clue.
Magnetism Test vs. iron staining Iron-stained surfaces can look like magnetite. Confirm actual attraction, not appearance.
Magnetism Test vs. magnet contamination Iron filings stuck to the magnet can transfer to specimens and create false “magnetic” behavior.
Magnetism Test vs. weak response Some minerals respond faintly. Record strength (strong/weak/none), not just yes/no.