Ceramic technology and paintings of archaic architectural slabs, louteria and antefixes from the Palatine Hill in Rome (Italy)

Abstract

Archaic Roman painted antefixes, architectural slabs and louteria from the Palatine Hill in Rome, Italy, were studied by non-destructive and micro-destructive methods: Portable X-ray fluorescence (XRF), micro-Raman spectroscopy, optical microscopy, scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD). The investigation enabled the characterization of raw materials and ceramic technology, providing insights on provenance. In fact, similarities were recognized with terracottas from the neighbouring Etruscan Veii. The analysis of pictorial layers revealed the use of Fe-and Mn-based pigments, as well as the identification of more precious pigments on worthy pieces. The research intended to support the archaeological discussion about the frame of the nascent city of Rome, also in relation to the coeval Etruscan culture.

X-ray Synchrotron Radiation to Look at Pigments in Antiquities: Overview and Examples

“…The second group consists of fragments of polychrome painted architectural terracotta found in the Palatine and Roman Foro in Rome, now preserved in the Colosseo Archaeological Park. They are unique pieces dating to the Late Archaic period (5th century BC), the production of which may be linked to both Etruscan and Roman workshops [86], characterized by polychrome decorated surfaces with tones and motifs similar to the Etruscan terracottas from Cerveteri [85,89,90]. Samples were taken from selected areas of the slab fragments.…”

“…In total, twelve microsamples from Cerveteri slabs (four black, three violet, three green/grey) and seventeen from Palatine Hill slabs (three black, one blue, two violet, seven red) were examined, selected to be representative of the color range observed on the architectural terracottas. Exploratory laboratory and in situ XRF and Raman analyses provided the basis for advanced investigations at synchrotron sources [85,86].…”

“…In the present study, two sets of materials, namely, architectural slabs from Cerveteri involved in a case of antiquities requisition [85] and decorated architectural terracottas from the Palatine Hill in Rome [86], were studied using SR-based X-ray methods to solve characterization problems that were not readily achievable using traditional nondestructive and noninvasive analytical techniques, such as portable Raman spectroscopy and X-ray fluorescence spectroscopy (Figure 1). Microsamples of pictorial layers were sampled by using a scalpel and analyzed by integrating and exploiting the possibilities offered by two different beamlines particularly suitable for CH materials at two different facilities, namely, the French Synchrotron SOLEIL and the Italian facility ELETTRA.…”

“…Heritage 2024, 7, FOR PEER REVIEW 8 red) were examined, selected to be representative of the color range observed on the architectural terracottas. Exploratory laboratory and in situ XRF and Raman analyses provided the basis for advanced investigations at synchrotron sources [85,86].…”

“…The available literature on black decorations on Etruscan architectural terracottas carried out using routine laboratory or portable methods [86,[88][89][90] indicate the use of Fe-and Mn-based pigments; different interpretations are proposed, namely, the use of manganese-black technique [92] or the use of natural pigments based on manganese and iron oxides [93]. The advantage of the manganese black technique lies in the possibility of obtaining the red and black color in a single oxidizing firing cycle, starting from a mixture of Fe-Mn oxides (probably hematite and pyrolusite) that forms a stable spinel-like phase, namely, jacobsite (MnFe 2 O 4 ).…”