Nice find! Did Norway have hallmarking for silver allowing you to identify the maker? The UK used to have extensive hallmarking for precious metals, but the rules were relaxed to more generic content marks (either parts per thousand eg 925 for Sterling silver, or carats) in more recent years and only expensive jewellers/makers seem to use full sets of hallmarks allowing you to date, value, place and identify the maker these days - we also lost some city hallmarking centres too with time…..