There is no town mark either and also as said the year mark is missing. That makes it a bit difficult. In addition, the crown mark is a bad punch. It could be an oval import mark (hardly but?). Anyway, the object is made (imported?) after 1912. Try to find more marks. Prospect HJ-makers are, Hjalmar Jonasson, Helge E. Johansson and Johansson's successor Bo-Åke Strandberg, but again but???? (too many buts here... sorry.