A combined analytical approach applied to Medieval wall paintings from Puglia (Italy): The study of painting techniques and its conservation state†. (8th October 2015)

• Record Type: Journal Article
• Authors: Fico, Daniela; Pennetta, Antonio; Rella, Giulia; Savino, Antonella; Terlizzi, Valentina; De Benedetto, Giuseppe Egidio
• Is Part Of: Journal of Raman spectroscopy. Volume 47:Number 3(2016)
• Page Start: 321
• Page End: 328
• Publication Date: 2015-10-08
• Subjects: kaolinite -- Medieval wall paintings -- pigments -- conservation state -- ion chromatography; Raman spectroscopy -- Periodicals; 535.846
• DOI: 10.1002/jrs.4813
• Languages: English
• ISSNs: 0377-0486

Abstract

Abstract : A combined analytical approach has been applied to the wall paintings, dated from 10th to 14th centuries, of the Santi Stefani crypt at Vaste (Lecce, Southern Italy). These paintings are a precious testimony of Medieval art in Southern Italy. However, the church shows problems of damp as well as clear evidences of flora, fungi and mold presence, and there is little knowledge of the pictorial methodologies used. Raman spectroscopy allowed to determine the palette and to reconstruct the worksite and the chronological sequence of the various paint layers. Kaolinite, calcite, carbon black, hematite, massicot, goethite, indigo and azurite were identified as pigments along with synthetic pigments, like phthalocyanine blue and chrome yellow. Attenuated total reflectance‐Fourier transform infrared spectroscopy suggested the presence of egg as a binder in some pictorial layers. The conservation state of the crypt is poor, and detachments of pigmented layers are frequent because of the presence of subflorescence and efflorescence: nitrate, sulfate and chloride salts have been identified spectroscopically and quantified by ion chromatography. The extensive use of kaolinite in Santi Stefani, actually not uncommon in Medieval art, is observed for the first time in a crypt of Puglia: its use to stabilize some pigments and to improve their adhesion on substrate is proposed. Copyright © 2015 John Wiley & Sons, Ltd. Abstract : As part of a multidisciplinary study on the artistic forms developed in Puglia, micro‐Raman, attenuated total reflectance‐Fourier transform infrared spectroscopies and ion chromatography were used for the study of Medieval wall paintings of Santi Stefani crypt (Puglia, Italy). Materials, techniques and degradation products have been identified, and the results obtained, sometimes unexpected, are discussed.