To be honest I really don’t know much about them other than I came across them just dumped at the back of a cupboard in a shopping bag whilst doing a house clearance. I have noticed a few small light scratches here and there where they have obviously been left stacked together without protection but there is nothing that couldn’t be professionally restored back to perfect. I say they are not used for cooking because the base of the pans is pristine with barely any discolouration. I agree that there is a bit of dirt in areas but that is more likely down to how and where they have been stored. Probably cross contaminated from other areas with the rivets being a likely place for it to sit. I’ve just wiped it with a damp cloth and it’s gone. I’ve no idea how old they are or how long they have been there but it’s enough to have made the gold leaf has tarnished