Ascione
A family firm established in 1855 and known for its traditionally made coral jewelry and artwork, Ascione has a showroom/gallery on the second floor of a shabby wing of the Galleria Umberto. Don't miss the 30-minute guided tour (€5, book ahead), which explains the company's rich history and takes in displays that include Egypt's King Farouk's elaborate wedding gift to his bride, Farida, as well as what many consider to be the most beautiful cameo in existence.