Silver rusting?

Hi everyone, hoping you can shed some light on what I'm seeing here.

This is just a little piece I recently made for a friend, but I'm confused as to what looks like rust showing up in some sections.
I'll attach an image to explain, it's pretty obviously discoloured.

Could it be from the Steel Wool I used to give this a rougher finish?

Any and all advice appreciated!

Attachment 13349

Yes it does look like rust, but if there were steel filaments in the silver, or incorporated in the solder, they would have turned your piece an obvious red in pickle.

My conclusion is that it is something the wearer has done and can easily be removed. I would give it a vigorous brushing with a wet and soapy brass brush. Dennis.

Thank you Dennis, I've been totally at a loss.
Will clean it up as described.