Polychromy in Ancient Greek Sculpture: New Scientific Research on an Attic Funerary Stele at the Metropolitan Museum of Art

Abstract

Polychromy in Ancient Greek Sculpture was the subject of the exhibition Chroma: Ancient Greek Sculpture in Color, held at The Metropolitan Museum of Art (The Met), New York, in 2022–2023. On this occasion, a multidisciplinary project involving The Met’s Departments of Greek and Roman Art, Objects Conservation, Imaging, Scientific Research, and colleagues from the Liebieghaus Polychromy Research Project in Frankfurt, Germany, was carried out to study an Attic funerary monument. The color decoration of the sphinx was reconstructed by combining non-invasive and minimally invasive techniques that provided information about surviving and lost pigments, original design, and painting technique. Results of multiband imaging, digital microscopy, and X-ray fluorescence spectroscopy guided the removal of minute samples from selected areas for examination by Raman spectroscopy and scanning electron microscopy, coupled with energy-dispersive X-ray spectroscopy, to shed light on the pigments and paint stratigraphy. The color palette included two varieties of blue, Egyptian blue and azurite, a carbon-based black pigment, two reds, cinnabar and red ocher, and yellow ocher, all painted directly over the marble without a preparation layer. The scientific findings informed the physical reconstruction of the sphinx made by archaeologists from the Liebieghaus Polychromy Research Project, featured in the exhibition.

pXRF and Polychromy: Identifying Pigments on Limestone Statuary from the Roman Limes, Preliminary Results

“…The black was identified as hydroxyapatite (Ca 5 (PO 4 ) 3 (OH)-bone black, previously considered less common than carbon-based blacks. However, emerging heritage materials science techniques have detected bone black in pigment mixtures on wall paintings, sarcophagi, and stele from Antiquity [45][46][47][48]. The previous SEM/XRD report suggested the green to be "Egyptian green" based on the presence of cuprorivaite, but it is herein confirmed as Egyptian blue (CaCuSi 4 O 10 ), a calcium-copper-silicate with a crystalline structure in use since the 3rd Millennium BCE in Egypt.…”

An Achaemenid God in Color

“…This suggests that the presence of arsenic with iron in some red areas analyzed by XRF may be a property of the specific red iron oxide pigment(s) used at Persepolis. Looking to ancient Greece, trace arsenic was detected in hematite particles on Attic sculpture [65] and in red pigment from the agora of Kos [66]. In contrast, Stefano Ridolfi and others [67] suggested realgar was used in areas of Darius's Palace and the Hall of Columns based on the detection by XRF of arsenic with iron.…”

Hydrophobic and Photocatalytic Treatment for the Conservation of Painted Lecce stone in Outdoor Conditions: A New Cleaning Approach

“…The application of painted layers on lithic materials, in both architectural and sculptural fields, was a very common practice in ancient cultures such as the Egyptian, Greek and Roman ones but also in the Romanesque, Gothic and Baroque periods up to modern and contemporary works [1][2][3][4][5]. Nowadays, traces of the original pictorial layers on the outdoor architectural works of art are rather rare, partly due to natural ageing caused by atmospheric agents (water, climate and pollution) and partly because over the centuries, there have been many interventions on the architecture or even just on the coloring of the buildings, adapting them to new styles.…”