british hall marks are strictly controled and are not put on by the manufacturer so cast hall marks on a british made item are illegal and prison sentences are still handed down for fake ,be they stamped or cast, marks
i believe this has always been the case with german hall marks??
i have no comments to add about the rest of the dagger but that top mount looks very amateurish and not up to any jewllers standard i think at best its a later addition pehaps copied from an original