Damp smell and marks on vintage skirt

[BadgerQueen]

I have a very lovely early 1970s Ossie Clark suit which has been in a cupboard for ages. The cupboard turns out to be damp and the skirt has brown and white marks all over the back of it. The label says dry clean only - but there is no information on what the material is - its black and soft with a sheen, like a very light suit material (oh its soooo lovely I can' bear it if it gets ruined) would it be safe to take it to my local dry cleaner or can I hand wash it myself. I want it clean and damp free before I store it properly. Any suggestions?

[TheProvincialLady]

If you have a museum with a textiles collection near you, then I would take it to the textiles curator for advice. They will be happy to do it.