So I take it electrolysis would be harmful to the coating. I think a vinegar bath will be the way to go then. The bottom doesn't have anything other than light rust and seasoning patina I could live with, a good cleaning should bring out all the writing that even now can be seen. I'm also starting up a lye bath, finally found some Rooto, but even if lye wouldn't affect the porcelain there is little need for it.