Painted plaster and glazed brick fragments from Achaemenid Pasargadae and Persepolis, Iran

Abstract

Background: Architectural fragments of decorated walls, floors, and columns excavated by Ernst Herzfeld at the archaeological sites of Persepolis and Pasargadae in Iran are housed in the Freer Study Collection at the Freer Gallery of Art and Arthur M. Sackler Gallery (FSG), Smithsonian Institution in Washington, DC. Technical studies of these painted earthen plasters and glazed brick fragments were undertaken to enhance our knowledge of materials and technology of Achaemenid Persia between the late sixth and fourth centuries BCE. Initial analysis was done on the surface of the fragments using non-invasive X-ray fluorescence with a portable instrument. Polished crosssections were used to examine the layering stratigraphy of paints and glazes, and to undertake compositional analysis using scanning electron microscopy with energy-dispersive X-ray spectroscopy.Results: Up to five layers of paint are present on the Pasargadae plaster, constituting the remnants of a geometric design. The plasters were bound with clay tempered with an organic material that has long since degraded, leaving small voids throughout. Pigments identified include Egyptian blue, malachite green, red ocher, and cinnabar red. The floor fragments from Persepolis were finished with a lime plaster and two layers of hematite-rich paint. The brick fragments from Persepolis were found to be composed of high-silica material similar to faience, which were decorated with alkaline glazes, including a yellow glazed colored with lead antimonate, gray glaze colored with magnesium and iron, and green glazed colored with copper. Conclusions:While the exact ages of the finishes are unknown, a similar technology was employed to decorate Achaemenid architecture in its principle Iranian cities. The variety of materials excavated by Herzfeld demonstrates the ability of Achaemenid artisans to work with multiple mediums to create a polychromatic finish including that of glazed tiles, earthen plaster tempered with gravel, earthen plaster tempered with organic matter, colored earths, pigmented paints and lime plasters. The layering of these materials can be seen and analyzed in cross-section although surface deterioration is often quite severe. The analysis of the compositional data on the architectural fragments inform their long-term preservation at the FSG as well as at the sites themselves.

Mineral Pigments in Archaeology: Their Analysis and the Range of Available Materials

“…Malachite mixed with green earths and yellow ochres has been identified at Roman sites in southern Germany [94]. Malachite and Egyptian Blue were found by Aloiz et al [129] and Stodulski et al [72] at Persepolis and Pasargadae.…”

“…Occurrences of Egyptian Blue in later Greek Classical and Hellenistic art are widely attested by Riederer [169,178], Kakoulli [172], Gassanova et al [66] and in Achaemaenid Iron Age architecture by Stodulski et al [72] and Aloiz et al [129]. By the Roman Period, manufactories of the pigment outside Egypt had become established and are documented by contemporary authors.…”

Recent progress in instrumental techniques for architectural heritage materials

“…Therefore, depending on the physical state, the chemical structures and the properties of the desired information, the PXRD test parameters and data analysis methods may vary greatly. In the field of architectural heritage, PXRD is one of the cheapest and most reliable technique to identify crystalline phases both in natural and man-made materials such as mortars [243,244], bricks [245,246], pigments [18,233], building stones [247,248] and so on.…”

Mineralogical–Geochemical Characterization and Provenance of the Stones Used at the Pasargadae Complex in Iran: A New Perspective

“…Abolverdi is one of a number of sites that possess raw materials similar to those used in the construction of the Tomb of Cyrus the Great (Aloiz, Douglas, & Nagel, 2016;Mohammadi & Krumbein, 2008). However, the precise site is still yet to be identified.…”