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Well,, My opinion is that it is a souvenir pin from someones trip to Italy !! You can find the cross and crown above in the square showing the mark variations of Naples !! Some of these are pottery marks !! The cross and crown is the symbol of the Royal Factory and the Royal family although the royal family would have an R for the factory or FR for the royal family !!
Since there have never been restrictions on the use of this mark you can find many variations !! The Fleur di Lis was also used in Naples thats why you have it in the broach as well !!
I think it was a memento of someones trip !! Looks like either antiqued brass or bronze pin !!
Couldn`t see if anything is on the back !!