The city mark is a crowned spear point or "strahl": the canting (punning) arms of Stralsund in Mecklenburg-Vorpommern, on the Baltic in far northwest Germany. The maker's mark is difficult to read, but I think is "JFD" for Johann Friedrich Dumrath (b. ca. 1790), the son of silversmith Martin Bermhard Dumrath and working ca. 1820-1840. The piece is an etrog box, used to protect the ritual citron during the Jewish holiday of Sukkot, the Feast of Tabernacles (which I believe is coming up in a few weeks).
Hope this helps!
Ref: Wolfgang Scheffler,
Goldschmiede Mittel- und Nordost Deutschlands (Berlin: de Gruyter, 1980), marks #940 & #981. See also this thread:
Eagle Mark