Patera ‘Love & Harmony' (Italy 13th century)

These architectural elements (roundel or ‘patera’) were integrated in the exterior walls of Italian houses (especially Venice) to ward off evil. They were highly fashionable during late 11th until 13th century, are Byzantine in origin and were made until the 15th century. Their diameter can go from 20 to 80 cm and they can be up to 10 cm thick. Next to the round form, there was also a rectangular architectural element, often ending in an arch, with the same sort of iconography. These are called 'Formelle'.
The patere have next to their esthetic dimension also a symbolic meaning: two fighting animals refer to the struggle between good and evil. Two birds with heads against each other and with entangled necks symbolize love and harmony.
The main entrance portal of San Marco has in the upper part of its arch several patere, among which two birds with interlaced necks.
Our patera is in good condition. Thick. Coarse greyish-white limestone.
Diameter: 27cm. Thickness: 6cm

References:
Metropolitan Museum New York (Accession Number: 09.152.11)
https://www.metmuseum.org/art/collection/search/463193

There is an exhaustive study of these romanesque patere and formelle. it is the standard reference:
“Romanische Reliefs von Venezianischen Fassaden ' Patere e Formelle ' Mit 165 Abbildungen im Text und 567 Abbildungen auf 88 Tafeln”
Swiechowski, Zygmunt / Rizzi, Alberto / Hamann-Mac Lean, Richard
ISBN 10: 3515029435 / ISBN 13: 9783515029438
Editore: Franz Steimer, Wiesbaden, 1982

Online:
Venice and its Lagoons https://www.venicethefuture.com/schede/uk/322-aliusid=322.htm

Le Patere di Venezia https://ekphrasis.it/5770/