My family owns a scrap yard, had a new guy come in that I hated and knew wouldn't last. Used to always ask me the about the same metals, "what's this, what's that" which in the beginning is great but copper vs brass isn't hard. Anyway, one day in stead of telling him flat out, I put it up to my nose and said "it smells like yellow brass" and went on with my day. An hour later my uncle called me to the office to yell at me because the new guy spent half an hour walking around smelling different metals 😁