Rusty?

You never know what you'll find when you get into a watch.  This one looked very clean from the back. It did not run, and the balance was not free, but in much of these cases that is only because of gummy old oil.  However, in the dial side, and under the ratchet wheel, there was quite a bit of staining from rust. Rust does has no effect the nickel plated parts, so it will come right off, but it is coming from someplace.