Just trying to research an old Avia I've had for years. Originally belonged to my grandfather who died in 1964. It's marked Avia DE LUXE self winding, was probably bought in London. Centre second hand, 17 jewels. Looks as if it was luminous at first. Case appears to be chrome plated brass. My father told me he hadn't been able to wear it due to corrosion where it contacts the skin. Same for me. Stainless steel back is, of course, not corroded. Back appears to have a model number, 3657.1. Movement is copper plated. Marked AS 1361 N Will add pics if I can find out how. Any idea of age? Any idea how I can stop the corrosion so I can wear it occasionally?