Birgit Angelika Schmidt

Clay-based sculptures are shown for the first time in dense displays in two galleries of the Museum für Asiatische Kunst (AKu) in Berlin's new Humboldt Forum. These artefacts were brought to Germany by the Turfan Expeditions (1902-14) 1 from Buddhist nodes along the ancient northern route around the Taklamakan desert (today´s Xinjiang Uyghur Autonomous Region). Grouped according to their archaeological sites, it is striking to note that almost identical heads and body shapes occur along the various oases, some of which are hundreds of kilometres apart. In this context, their variations can be considered as a phenomenon of modular production. This can be impressively illustrated in the Buddhist architectural layout along the edges of the lowlands of the Tarim Basin through the materials and production techniques of these sculptures. Although the compositions were limited by the naturally occurring materials, the modular character of their production made it possible to create an extensive variety in terms of details. In this pilot case study, two objects are selected to illustrate this modular system.

A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified.

Based on the four German Turfan Expeditions, which between 1902 and 1914 travelled mainly to the sites and nodes along the route at the northern edge of the Taklamakan Desert, this paper discusses the extent to which the extreme arid climate and vegetation influenced the choice of local building materials and construction methods in architecture, as well as the development of artisan production. The basis for these investigations are the archaeological traces and materials that remained in situ as well as the material collected by the German explorers, which is housed in the current collection of the Museum für Asiatische Kunst. I shall focus mainly on the wall paintings and sculptures detached from their architectural context. The records, photographs, drawings and archaeological reports made in the course of the German expeditions form an additional, important source of information.

This paper is focussing on wall paintings from the Museum für Asiatische Kunst in Berlin, Germany. Their original painted surfaces are blackened with soot and are largely illegible. They were already detached in this condition in 1906 during a German expedition to the Northern Silk Road (nowadays Xinjiang, People's Republic of China). Due to the removal from their actual site and the concomitant loss of the original function of these objects, they are subjected to different processes of de-and recontextualizations. Investigations aim to contribute an overall picture to the fragmentary wall paintings. Methodical techniques, but also their limits and problems, are discussed in this paper. To visualise authentic images and to transform them into today's museum's context are among the great challenges of this work. Within the project, the authors discuss different tools that support the aim to identify the traces of the past.

Many wooden artworks are contaminated by DDT (dichlorodiphenyltrichloroethane) as a result of a surface treatment by means of the liquid preservative Hylotox-59 ©. It was used until the end of the 1980s. DDT crystal structures are formed on the wood surfaces by the "blooming" of chlorine compounds. In addition to an aesthetic disturbance, it is assumed that DDT represents a health risk. Even decades after applying, the toxins in the wood preservatives are still detectable because they are of low volatility in many wood samples. Contaminated waste wood with natural biocide ageing, gilded and wood carved elements of an old picture frame and wooden samples with paint layers were provided by the Schlossmuseum Sondershausen. Non-contact procedures using laser and plasma appear reasonable to remove the DDT crystals. During the experiments, health and safety issues for the operator have to be taken into account. The removal of DDT was evaluated employing femtosecond and nanosecond laser radiation and cold atmospheric plasma techniques with different working gases (air, nitrogen, and argon). Before laser application, a chlorine measurement representing the DDT density on the wooden surface is done by X-ray fluorescence (XRF) analysis as reference. After laser processing, the XRF analysis is used again at the same surface position to determine the depletion rate. Additionally, a documentation and characterization of the sample surface is performed before and after laser and plasma treatment using optical microscopy (OM). For plasma processing with various systems a chlorine measurement is done by gas chromatographic-mass spectrometry (GCMS) analysis.