Iron filings are very small pieces of iron that look like a light powder. They are very often used in science demonstrations to show the direction of a magnetic field. Since iron is a ferromagnetic material, a magnetic field induces each particle to become a tiny bar magnet.
Pure iron filings quickly oxidize (rust) and can be messy. Flinn’s iron alloy metal filings act just like iron filings for magnetism experiments, but resist oxidation. Use pure iron filings for iron sulfide or other chemistry experiments.
I 1495 (OTTO) Iron, fillings, 100 mesh, 99% Cas 7439-89-6 - used at the active site of many important redox enzymes.