the outstanding member of a family of Sicilian sculptors and stucco workers. His methods for creating the illusion of perspective and his asymmetrical arrangements of two or more independent decorations proved highly influential to German artists of the Rococo period.

In Palermo, Giacomo decorated the oratories of San Lorenzo (1690/98–1706), San Zita (1668–1718), and Rosario di San Domenico (1710–17), as well as the Palermo hospital chapel, the Archbishop's Palace in Santa Chiara, and the Badia Nuova at Alcomo. His statues in San Francesco d'Assisi (1723) appear to be falling from air and not attached to the wall, even though all the figures, cupids, draperies, and garlands are on the same plane as the wall. He is credited with raising Sicilian stuccowork from a craft to an art.