I ron
Iron, in the form of fine filings, will burn and can be used to produce attractive gold sparks, such as in the traditional wire sparkler. The small percentage (less than 1%) of carbon in steel can cause an attractive branching of the sparks due to carbon dioxide gas formation as the metal particles burn in air.
Iron filings are quite unstable on storage, however. They readily convert to iron oxide (rust - Fe2 03) in moist air, and filings are usually coated with a paraffin-type material prior to use in a pyrotechnic mixture.