A friend who is a collector of military equipment has some canteens from the early 20th century. He is trying to determine if the composition is an ordinary steel with little or no chrome or if it is a type of magnetic stainless steel which has a higher amount of chrome.
It is pretty amazing what some people find interesting as a hobby, but this the stuff he does and he is really good at it. He has written articles about things like post-civil war cartridge belts.
Can anyone explain how to distinguish steel with chrome from steel without chrome (both magnetic) without expensive lab equipment? It is best if it is not destructive, but he is willing to remove a small amount of metal.
Rick