Investigation of post-restoration salt weathering at the mosaics of Dafni Monastery, Greece

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Published: Jun 17, 2024
DOI: https://doi.org/10.12681/monubasin.8348
Keywords:
Dafni Mosaics salt damage IR Thermography
Ekaterini Ftikou
Petros Prokos
Alexis Stefanis
Abstract

Dafni is an 11th-century Byzantine monastery in the suburbs of Athens and a UNESCO World Heritage Site. The main church of the monastery preserves a unique complex of wall mosaics from the early Komnenian period (ca. 1100AD). The building suffered many structural problems, especially during the 1999 Athens earthquake, when the poor state of the building significantly affected the mosaics. Thus, a great restoration program was initiated. After the completion of restoration and conservation works in 2016, the mosaics presented soluble salt efflorescences and consequent disaggregation of a specific type of tesserae produced from marlstone. In order to investigate the pathology of the mosaics and study the weathering mechanisms a methodology was developed. The approach was based on non-destructive testing techniques (NDTs) combined with microclimatic monitoring and instrumental analysis. Data correlation from NDT and laboratory analyses suggests that weathering is a result of water retainment within the masonry. Depending on the microclimatic conditions, aqueous solutions evaporate through the marlstone tesserae, triggering salt weathering mechanisms.

Article Details
  • Section
  • Part IV - Methodologies for Characterization and Damage Assessment

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Author Biographies
Ekaterini Ftikou

Directorate of Conservation of Ancient and Modern Monuments Athens, Ministry of Culture Athens, Greece

Petros Prokos

Directorate of Conservation of Ancient and Modern Monuments Athens, Ministry of Culture Athens, Greece

Alexis Stefanis

Department of Conservation of Antiquities and Works of Art, University of West Attica, Athens, Greece

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