Plaster application marks and their function in the 16th century Great Siege wall painting cycle, Valletta, Malta

Abstract

The Great Siege wall painting cycle in the Grand Master's Palace, Valletta, Malta, was created by the Italian artist Matteo Perez d'Aleccio between 1576 and 1581. Painted in the fresco technique, the cycle has a total area of 225 m² and depicts the events of the 1565 Great Siege of Malta in twelve narrative scenes. This paper reports on the examination and analysis of plaster application marks and plaster composition of the Great Siege wall paintings, contributing to the conservation of the cycle implemented from 2018–2023 by the Department of Conservation and Built Heritage (DCBH), University of Malta. The study explores plaster application marks, possible adaptation of the plaster composition to the Maltese material context, potential correlation between the plastering technique and its condition, and conservation implications using complementary non-invasive and invasive methods (PLM and SEM-EDS) .