I have an old iron/steel/whatever wok that I used to use a lot, but I thought I'd cook something with it today but when I dug it out of the cabinet, it was rusted. There was rust all inside of it. Whoever used it last must have put it away wet or something So, I used some steel wool to get all the rust off, but there's still a rusty color to the metal that no matter how hard I scrub it just doesn't come off. So, I'm wondering... is this ruined and I may as well toss it and get a new one, or will I be able to cook with it now the way it is? It's clean as far as I can tell, it just appears to be discolored in parts... Any ideas?