Types: Patere and Formelle
Patere are the small, typically circular reliefs that dot the sides of buildings throughout Venice. Their shape originates from the way they were made, often sculpted from slices of old marble columns that had been replaced in past renovations of a building. Usually 20 to 80 centimeters across and only eight or so centimeters deep, patere exist in six categories: flat, low/medium relief, high relief, curved, champlevé, and drilled, named according to their sculptural topography. Flat patere are the oldest category. 
Fashionable in the 12th to 14th centuries, patere were seen by Venetians as superstitious charms that could protect a household from vice or evil, keeping it at bay. The motifs on patere are widely varied, with about 150 different images accounting for the majority of their designs. One very common image is that of an eagle eating the head of a rabbit, representing the victory of virtue over vice. Another common theme, thought to represent harmony, depicts two flamingos with their necks intertwined, sometimes drinking or eating from the tree or fountain of life.
Patere are products of Byzantine culture, a dynasty that produced many Venetian treasures. They are also the oldest type of Venetian public art. Formelle, a related type of public art, are also considered part of the patere collection, because they share many of the same graphical motifs.
Formelle are larger than patere, and are characterized by a rectangular shape capped with a rounded arch, rather than being circular.
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