Mormon is typical of Naples, Mormons, seems to be unique and it is almost certainly due to an error in transcription by an officer of the northern registry, it is possible to exclude a derivation from the Mormon sect as it arrived in Naples in the early 1900s , while the Bourbon registry office was already operating in Naples from 1810.
Buy a heraldic document with your coat of arms
Verba Volant, Scripta Manent