A lot of east bloc dentistry used to use ferric metals. I wonder if they still ask about dental work before an MRI.
I believe tattoo ink has metal in it. Lotsa tattoos out there. That would really make them “hot.”
That would be stainless steel for the most part. Most grades of SS are not ferromagnetic so no problem there. Heat treatable grades of SS (enough carbon content) are generally used for things like knives (various cutting implements) and springs. I have a handful of titanium surgical clips in my gut and have had no problem with them during multiple MRIs.
An attendant was killed while getting a patient settled in the MRI when the operator switched on the magnet and an oxygen bottle flew across the room and fractured the attendant's skull.
Regards,
GtG