Following French marking convention the Z (if that is the initial) would be the first name, or if a partnership could be the initial of the surname. In either case, you’d look up the maker in various dictionaries and databases under Z. Example: Z, symbol, second initial.
If you clean out the mark properly, you might decipher both the symbol and second initial.
Also, before you begin to look up the maker you’d have to determine if the object was made in the provinces or in Paris by looking at the silver standard mark. If you don’t have this basic info, it would be a long and involved chase for the name of the maker.