The first part of the results of the current research regarding the Acropolis monuments’ polychromy is presented in the scientific study of Dr. E. Aggelakopoulou, head of the Conservation Department of the Acropolis Restoration Service (YSMA) and Associate Professor of the School of Chemical Engineering of the National Technical University of Athens, A. Bakolas, entitled “What were the colors of the Parthenon? Investigation of entablature’s cornice blocks”, which was recently published in the prestigious peer-reviewed International Journal of Archaeological Science (https://authors.elsevier.com/ a/1eZKJ15SlTv9Jp).
This work is part of the first systematic investigation of the ancient polychromy of the Parthenon and the Propylaea, research which initiated in 2015 and is still in progress. The study contributes to the wider scientific research on ancient architecture, promoted through the restoration work carried out by YSMA under the guidance of the Committee for the Conservation of the Acropolis Monuments, and in collaboration, when necessary, with research organizations (NTUA).
The aim of the ancient polychromy investigation is to document the design motifs of the architectural members, determine the conservation state of the paint layers and the marble surfaces, as well as to characterize the pigments and binding materials used for the paint layers. By gathering this information, our knowledge regarding the ancient painting technique on marble and the decoration of ancient temples and sculptures is enriched and a more precise image of the original painted surface of the monuments can be obtained.
This work presents new insight regarding ancient polychromy and more specifically:
- The pigments used to decorate the horizontal cornice blocks of the Parthenon, which have survived until today, are blue (azurite, Egyptian blue), red (red ochre, lead red) and green (conichalcite).
- Different pigments of the same color were deliberately used by ancient painters to depict different designs on the same pattern; this allowed them to achieve special chromatic hues and tonalities on the two patterns of the taenia, thus enhancing the final aesthetic effect.
- Regarding the painting methodology applied, the research results reveal that the first step was surface treatment via the carving process, aiming to increase surface roughness and enhance the adhesion of the paint to the substrate. Afterwards, the pattern was incised on the marble surface. In the case of geometrical patterns, horizontal and perpendicular lines were incised to create a grid of tetrangular shapes. The pigments were applied directly onto the marble surface without the application of a preparatory layer. In most cases, the surviving paint layers present an excellent adhesion with the marble substrate up to today, millenia after their application.
- The presence of beeswax is detected for the first time in paint layers of an ancient monument exposed in an open-air environment. The presence of beeswax is in line with ancient inscriptions, which referred to the encaustic technique for the decoration of ancient monuments.
- The scientific results that emerged are compared with written sources and representations of 19th century scholars. Scientific research not only confirms part of this data, but also provides new findings, developing a new perspective on the polychromy of the Acropolis monuments.
The study was based, at first, on the application of in-situ imaging techniques (which do not require sampling), conducted by the personnel of the Conservation department of YSMA. Following this investigation, the laboratory techniques of Stereomicroscopy, μ-Raman spectroscopy, ATR-FITR spectroscopy and Scanning Electron Microscopy with energy dispersive X-ray technique (SEM/EDX) were applied on micro-samples that were selected from the preserved paint layers of the cornice blocks. The laboratory techniques were applied at the School of Chemical Engineering of the National Technical University of Athens, by Dr. E. Aggelakopoulou, in the framework of her postdoctoral research supervised by Assoc. Prof. A. Bakolas.
This study comprises innovative research and highlights Greece’s scientific expertise and technical ability to preserve and highlight ancient architecture and sculpture.
