I just purchased a piece of costume jewelry. It has 5 large, rectangular stones with large links between each stone. The clasp has what appears to be 885 with a fish symbol behind it. Any ideas on what this means?

These sites might give you some information:

http://www.google.com/search?hl=en&ie=ISO-8859-1&q=jewelry%2C+fish+symbol&btnG=Google+Search