thanks Cathy - will probably try just metal polish to start with, and if no improvement will add either some cerium oxide or possibly tin oxide - these are both used in the jewellery and optic professions (via a power line of course) If still no good, I will smear lightly with vaseline, and pretend there was never ever any staining in the first place
(or something similar that was suggested in recent weeks - I forget the exact words or by whom). Will let you know if it works.
jp - my sincere thanks for your words of comfort and support. Personally, I think that Webb's pieces are a worthwhile output to collect, aside from the fact that I tend to favour pre second war material, they are interesting and possibly under-rated still. Paul S.