Il Fortino Lorense a Forte dei Marmi: caratterizzazione petrografica dei materiali e tecniche di restauro

The Fortino Lorenese in Forte dei Marmi, a town sited in the province of Lucca, was built in the 18th century, during the Grand Duchy of Pietro Leopoldo d’Asburgo Lorena. Realised to play the double role of coastal defense tower and customs, it is composed by a three-floor, plastered building sided by a rough bastion with rounded corners, oriented towards the sea. During the quadriennium 2020-2023, a two-phase project was undertaken to restore its external surfaces. The first phase of the project was devoted to the characterisation of the bedding mortar of the brick vestment by conducting a petrograhical analysis on a wall sample and a classification of the lithotypes employed to construct the marble elements of the bastion. Such a characterisation allowed the state of conservation of the Fortino Lorenese to be established by clarifying the nature of the degredation mechanisms acting on the brick and stone rough surfaces. During the second phase of the project, the study of the processes that altered the plastered surfaces and stone cornices of the fortress revealed that their state of conservation was compromised by the restoration carried out in 2013, during which materials whose physical properties were not compatible with the ones of the support were employed. A thorough study of the colours that have been employed to paint the Fortino Lorenese across its history has led to novel hypotheses about its appearance at the time of the construction. The choices animating the project couldn’t ignore the reputation gained by the fortress as Palazzo Littorio, leading us to opt for not bringing the building back to any of its previous versions, as this would have canceled the traces of its passage through time.