The mitre is a masterpiece of goldsmithing commissioned in 1712 from the goldsmith Matteo Treglia, intended to adorn the bust of Saint Januarius during the May procession. Crafted from gilded silver, the mitre draws inspiration from the embroidered fabric of episcopal mitres and incorporates 3,326 diamonds, 198 emeralds, and 168 rubie, with a total weight of a remarkable 18 kg! The stones were chosen to represent the three theological virtues: diamonds for faith, rubies for charity, and emeralds for hope. Among the most notable gems are a Ceylonese ruby called “Vesuvius Lava” and a teardrop diamond with an innovative brilliant cut for its time, which was the most expensive part of the composition. The largest Colombian emeralds bear the names of the members of the Deputation. The back of the mitre features two gem-encrusted infulae (lappets), with engravings of Saint Januarius’ ampoules, the names of the patrons, and the inscription “Matthaeus Treglia fieri curavit,” indicating that the work was the result of coordinated effort by Treglia with dozens of other masters.