I'm wondering if anybody recognizes the maker's mark "JD" (appears within a mark that looks like a ring); the brooch is also marked "935" and "depose," so I gather it's French or German?
LOL - I got all excited while researching the marks on another piece I just got, then I realized this was my own post from 5 years ago that never got resolved... Here's the new piece by the same maker:
This is French, I believe it to be by Joseph Dizy a master silversmith working around 1920. I will check some old books to see if I can find out any more.