Theres a scrap metal place not far from my home. About 6 months ago I took some scrap from work there to sell and the guy had a 'gun' (kinda looked like a police radar gun) that he set against the steel for 10-15 seconds and it told him exactly what the scrap had in it,,, %'s of nickel, iron, manganeese, carbon, etc... it was quite a cool item, maybe a scrap metal place close to you or a steel store might have the same kind of tool....
-M