On the Technology of Central Asian Wall Paintings: The Problem of Binding Media

Abstract

Organic components of paint layers and grounds in specimens of late antique and early medieval Central Asian wall paintings were studied. Quantitative analysis of amino acids isolated from specimens of Mansur-Depe wall paintings, second to first century B.C., has demonstrated that gelatin was used for the preparation of painting media and grounds-proline, glycine and alanine were revealed to a high percentage while hydroxyproline was not detected. In other wall paintings of the second to the eighth century the use of plant gums was inferred since polysaccharides isolated from the specimens had infrared spectra resembling those of polysaccharides from the Prunoideae sub-family. The gum used in the Toprak-Kala wall paintings, third to fourth century, and in a nineteenth-century painting from Khiva could be identified precisely: it was either apricot or cherry gum. The technique used for the preparation of paints and grounds in Mansur-Depe and Kara-Tepe, second to fourth century, resembles those described in medieval Indian manuscripts. the Bactrian Buddhist temple complex of Kara-Tepe, second to fourth century [4J; the Khorezmian palace of Toprak-Kala, third to fourth century [5]; houses of Sogdian city nobles in Pendjikent, seventh to eighth century [6]; the Buddhist temple of Adjina-Tepa, seventh century [7]; and the Tashkhauli palace, 1830, in Khiva. MATERIALS AND METHODS Samples of Paintings 1 -From Mansur-Depe-smallfragments with red paint on a relatively thick (2-3 mm) ground. The paint must have been Inade of Kzyl-kessak (a kind of ochre) as a pigment [3]. The ground consists of chalk with fillers: pounded ceramics and small pebbles [3]. It was placed on the mud plaster. The samples were collected in the portico (aiwan). 2 -From Kara-Tepe-fragments with red paintings and a fragment with a polychromatic painting from the P-II cave temple. The paintings are made on a ground 1-5-2-0 mm thick. The ground is different from that of Mansur-Depe. It is looser than the latter, almost insoluble in HCI, and with sand as the filler. The ground must have been spread in thin layers. The uppermost layer just below the painting is the finest and whitest one. The ground was placed over the sandstone walls of the cave. 3 -From Pendjikent-fragments of a thick clay plaster with fillers. A thin layer of white ground is over it. The colouring is black and brownish (the pigments are soot and ochre [8D· On the technology of Central Asian wall paintings: the problem of binding media 9

Matrix Assisted Laser Desorption Ionization Mass Fingerprinting for Identification of Acacia Gum in Microsamples from Works of Art

“…in Ancient Egypt . Arabic, tragacanth, and fruit tree gums such as apricot and cherry have also been detected variously in mural paintings in Greece of the 4th–3rd centuries B.C., Asian wall paintings of the 2nd–19th centuries, and in manuscript illumination of the 16th century . A major artistic use of plant gums since the 18th century has been as a medium for watercolor paints .…”