Growing up, the only railroad tracks I ever saw were old tracks, because no new lines were being built, and I didn’t expect them to be any other color. After all, any time you see tracks in films or IRL, they’re always that same rusty reddish brown, right?
Flash forward to 1990 or so, when L.A. began building out its transit system. We’ve put in several new rail lines since then, and I now notice the same thing–brown tracks. So what I’d like to know is this: Are the rails purposely pre-oxidized before being laid down, because you need to do that for some reason? For that matter, come to think of it, just about all structural steel seems to be oxidized in the same way. A brand new bridge is hardly ever shiny, after all. That must be for a similar reason–so please tell me what it is?