RESEARCH METHODS AND METHODOLOGICAL PROBLEMS DURING RESTORATION OF PREHISTORIC POTTERY. PART І

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1 Geoarchaeology and Archaeomineralogy (Eds. R. I. Kostov, B. Gaydarska, M. Gurova) Proceedings of the International Conference, October 2008 Sofia, Publishing House St. Ivan Rilski, Sofia, RESEARCH METHODS AND METHODOLOGICAL PROBLEMS DURING RESTORATION OF PREHISTORIC POTTERY. PART І Dimcho Radev 1, Alexander Sultanov 2 1Academy of Fine Arts, 1100 Sofia; radevi@abv.bg 2 University of Mining and Geology St. Ivan Rilski, 1700 Sofia; a_sultanov@abv.bg ABSTRACT. We present the first part of papers, treating the methods and methodological problems related to restoration of archaeological valuables and monuments of material culture. This part of study gives prominence to the main principles of restoration and secondary restoration (re-restoration) of anthropomorphous and zoomorphic ceramic plastic arts so called prehistoric beaten clay equipments. In this case three basic groups of archaeological objects for restoration are presented: archaeological objects, which are emblematic for some historical periods and cultural groups, that were restored 10 years ago or more and now are part of an exposition; archaeological objects, which are in safe-keeping in depository and are planned for restoration; archaeological objects, which will be exposed in situ after their restoration. Restoration of archaeological valuables and monuments of material culture is a science with great development. During the last 25 years the applied research methods provide maximum information about the state and authenticity of the original during its preliminary study. More preliminary information can be obtained during the investigation of the object in terms of orientated lighting with light source parameters, close to those of the natural light, as well as in infra-red and ultra-violet parts of the light-spectrum. X-ray examination and documentation on an X-ray photograph provides very important information about objects, related to icon-painting tradition, easel painting and polychrome over organic materials. During the process of study and documentation of prehistoric pottery the above mentioned methods provide only marginal part of the necessary information about structural peculiarities of the original and its art decoration. The data, obtained by the visual study and documentation with the help of stereomicroscope is not sufficient. The attempt to compare the results of earlier investigations on the mineral composition with some stage of heating to those of the initial source of raw materials and artifacts, which were found in situ, as well as the technology of their manufacturing is successful. The methodology of the restoration is predetermined by the technological processes of the pottery production, the sources of raw materials, the type of clay, the mineral composition of the art decoration, the type of inert fillers and the porosity of the structures. Scholars in Bulgaria are orientated to research centers in the Universities because of the lack of laboratory with special contemporary equipment for the above mentioned kind of investigations. The first efforts in 1980 were associated with the sole resources of the Laboratory at the Institute of Forensic Science, with the conscientiousness of Prof. Dobrinka Stavrakeva of the Mineralogy and Petrography Department at the University of Chemical Technology and Metallurgy and with the enthusiasm of the lecturers from the Department Conservation and Restoration Prof. Nedyalko Nenov and Prof. Mikhail Enev, and the Head of Photolaboratory Sen. Res. Associate Christo Etropolski and the Head of the Department Silicate Forms, Academy of Fine Arts in Sofia Prof. Georgi Kolarov. The first investigations were characterized by some fluctuation, but they laid the foundations and determined the trend for the future. The analysis, made in the laboratory at the Department Mineralogy and Petrography at the University of Mining and Geology, were more convincing (Sultanov, Radev, 1999). Most important for the authors of this paper is the definition of individual task and purposes for each object. During the 1980s the main principles of restoration and rerestoration of anthropomorphic and zoomorphic ceramic figurines and vessels, of the so called prehistoric beaten clay equipments and of the ever expanding group of Thracian rectangular fireplaces, called Thracian escharae (always made and kindled in situ ) have been differentiated. The group of furnaces for ceramics firing is with similar characteristics. In this way by the end of the above mentioned decade a multidisciplinary team was formed to study the archaeological valuables from the prehistoric period, made in one of the most resistant materials burned in situ beaten clay equipments and anthropomorphic and zoomorphic ceramic figurines and vessels. 353

2 The philosophy of the re-restoration is to achieve unification of: successful techniques for restoration; scientific research methods; optimum documentation of the main stages and processes; contemporary aesthetics of exposition. Unfortunately, the notes and publications concerning the sensational findings (the so called media archaeology ) of archaeological valuables during the last years do not go beyond their visual description. The serious findings require extensive research equal in value with the analysis of literary sources and the search for similar objects from the same historic periods. The growing necessity to popularise the spiritual and material culture of our predecessors and our identity in the globalizing world, require an active and attractive informational and advertising material as well as research publications in which a great part of the restoration documentation finds broader application. Now we have almost two decades of experience in this field and we expect from the archeologists to take advantage of the valuable information in our reports in order to support successful interpretation of the important objects from the Early Neolithic in Bulgaria. The requirement of expert intervention is of a great importance especially in the cases of aggressive atmospheric surroundings or extreme archeological excavations. The very restoration activity in the sense of repeated act toward the cultural and historical wealth now is expressed in prevention and permanent monitoring, which require the efforts of experts cooperated in a multidisciplinary team. During the last few years this multidisciplinary approach is realized as international teams. According to the mentioned purposes, the process of restoration and re-restoration go beyond its frame of reference and it is directly related to the activities of cultural and historical heritage protection on a regional, national and world level. Essence and necessity of secondary restoration (re-restoration) for prehistoric archaeological objects The essence of the process of secondary restoration (rerestoration) is to follow two fundamental requirements that concern very important archeological objects: complex investigation of the structural characteristics of the original; restoration and preparation for exposition in museum or in situ according to the contemporary aesthetics. In the present paper the most favourable situation for every single archaeological artefact is not under discussion. This is the case when the expert restorer carries out the field restoration during archaeological excavations. Only in this case the authenticity of the archaeological object can be preserved in an optimal degree. Unfortunately, in our country this kind of work is extremely rare. Unfortunately, the exposition in situ is another specific subject (closely connected to field restoration), which is still a good intention rather than a practice and will be presented in a separate study. In Bulgaria the re-restoration came into being as a necessity. During the 1980s when the above mentioned requirements were applied to important prehistoric objects from the main exposition in the Museum of Archaeology in Plovdiv, the rerestoration became clearly formulated. The main goal during the process of re-restoration was to make investigations in order to obtain maximum information about the decoration, structural characteristics and technology of the production of a unique ceramic vessel. Subsequently, the traces of its religious use have been found, but unfortunately they were not noted by the archaeologist Peter Detev and by mistake they were even filled with gypsum. Since its finding till now the object from the village Muldava, representing a Deer, is still one of the most significant zoomorphic ceramic vessel found in our country (Fig. 1-2). During the last two decades the efforts of the authors of this paper were orientated to the theme of re-restoration and investigation of the objects, which have undergone polymer treatment during their initial restoration. Usually this theme includes the following four main components: presentation of the specificity of the concrete archaeological object; determination of the research methods according to the specific character of the archaeological object; preparation of the methodology about restoration processes and stages in its realization according to the results of the performed analyses; an exposition in conformity with the contemporary equipment with additional visual and text information. The forms and aesthetics of the exposition are in compliance with the topical requirements of the various consumers groups of the cultural and historical heritage. Independently of the place of exposition in the museum or in situ our activities are predetermined by the essence of the museum institution as a cultural and educational institution, which presents to the society the spiritual and material culture of our predecessors. Each valuable archaeological artefact with complete restoration and research passport acquire socialization by including it in the expositional and educational programmes and products. In confirmation of this, it is necessary to add that now in the utmost degree these requirements are performed in the British museums. There the access to visitors from all over the world is unrestricted and offer a maximum degree of additional information according to the level of the consumer. Fig. 1. Deer from the prehistoric site near the village of Muldava, Asenovgrad Region (after P. Detev) 354

3 In every regional museum in Bulgaria various unique anthropomorphous and zoomorphic ceramic figurines, vessels and ritual ceramics from the first above mentioned group are on display or in safe-keeping. One example can be given. The ceramic bowl with unique artistic decoration performed with gold pigment (Fig. 3). Only one of the pointed requirements will be enough to prove an assertion that this object which has been exhibited all over the world, now strikingly is in need of re-restoration. That is why the study of even a small fragment can provide enormous information about the significance of this Chalcolithic ritual vessel (Fig. 4). The process of the polymer flowing and carbonate coats elimination of the original, as well as the restoration of the fragments, which are not stick well is possible. Investigations of the structure, decorative coats and technology of production enrich the scientific knowledge about the methodology of application of the oldest gold decoration of Europe. Fig. 2. Detail of a cult trace on the neck of the Deer from the prehistoric site near the village Muldava (photo Forensic Science Laboratory, 1980) Archaeological objects with no less significance for the Thracological science, the so-called Thracian escharaes from the Palace complex of Seutopolis are referred to the second group. This project started in 1990 in relation to the investigations of the Thracian escharaes in Bulgaria and Europe (Fig. 5, 6). Part of the process of re-restoration of the Escharae from the Palace complex on Nebet Tepe in Plovdiv is also related to this project (Fig. 5). This paper presents the three main groups of archaeological objects for restoration: archaeological objects, emblematic for a concrete historical period and cultural group which are in an exposition and without restoration more than 10 years; archaeological objects, which are on safe-keeping in depositories and are planned for restoration; archaeological objects, which can be brought for study in laboratories and will be exposed in situ after their restoration. Fig. 3. The investigation on the technique and technology of production and the traces of use can enrich the interpretation (vessel with gold pigment from the Varna II Chalcolithic necropolis, researcher I. Ivanov; photo D. Radev, 2008) 355

4 These two groups illustrated the significance of the archaeological objects from the depositories and the exhibition halls. They are cultural and historical valuables. Obviously, the most valuable objects are in the museums and this puts the question about their investigation, restoration and exposition in their best. The third group is presented by objects, which have passed full cycle of restoration processes from their lifting from the field to their exposition in the museum hall. One of the most important processes in the archaeological field work is drawing out the conflict zone between the structure dampness and the consolidation one, possibly more inside and asides. This process predetermines the stability of structure of the original surface during the elimination of the layer of soft protecting materials (Fig. 7). Fig. 4. This extremely small fragment compared to the scale and significance of the Chalcolithic ritual bowl can give very rich information (photo D. Radev, 2008) The photo documentation of the report on this theme displays the process of lifting of the escharaes from the complex of Seutopolis (on the basis of literature sources 35 wooden boxes with fragmented escharae required gypsum and fillers). During the process of investigating, another unique object is established the wall-painting decoration in the throne-room of the Palace complex of Seutopolis. All this expects restoration since 1952 when the archaeological excavations have finished and the ancient town of Seutopolis was left under the water of the dam G. Dimitrov (today Koprinka ) near Kazanlak. Fig. 7. House oven with imprinted decoration from the Slatina site in Sofia (researcher V. Nikolov; photo D. Radev) The state of the archaeological objects which have been restored more than 10 years ago and main reasons for the necessity of their rerestoration Unreal and insufficient visual contact to the original; deformed polymer and gypsum suffusions on the surface of the original; preservation of the art decoration and symbolics of the original; unsuccessful restoration of the completeness of the object; discredited exposition of the object; cracked and deformed foreign to the object materials; lack of text and photo documentation. Fig. 5. Еscharae from the Palace complex (detail) at Nebet Tepe in Plovdiv (researcher A. Peykov) Aims: to take the object out of the position of unconvincing representativeness of the cultural tradition; to perform a complete research of the specific structural characteristics of the object and its decoration; to document and systematize the results in a complete restoration passport; to identify the actual status of the object; to eliminate the secondary layers from the original surface; to prepare the original stick seams in order to recover wholeness of the form and decoration of the object; to stick together the fragments in order to get optimal wholeness of the original form and to stress on the authenticity of the original; Fig. 6. Еscharae (detail) from the V. Levski site (researcher K. Kissiov; photo D. Radev) 356

5 to systemize the research results and to prepare the methodology of re-restoration and variants of object exposition; to recommend the prevention of the objects. Comparison between the initial restoration and specifics of the secondary restoration process As at the initial restoration activities of importance are the atmosphere aggressiveness, the rapid dehydration of structure and decoration with additional destructural processes. During the re-restoration the processes take the reverse order a control reversity of all the processes and a maximum preservation of the original during the removal of secondary covers and materials, which discredit the significance and replace the authenticity of the original (Fig. 8, 9). Fig. 9. Secondary changes on the plastic decoration of Base for a cult column (detail) from the Slatino site, Sofia (researcher V. Nikolov; photo D. Radev) For the objects from the first group the aim is controlled replacement or deviation of the terrain dampness, the so called conflict zone between the moisture and the infected dissolve reagent compresses for a consolidation of the original structure. During the processes of re-restoration with the help of dissolve-reagent compresses a controlled reversity of the processes is obtained in order to relieve the original and to expose its authenticity according to the actual aesthetics and the supporting graphic and 3D restoration designs with supplementary photo documentation. References Sultanov, A., D. Radev The clay a beneficial archaeological material. Minno Delo i Geologia (Mining Affair and Geology), 1-2, (in Bulgarian). Fig. 8. Base for a cult column from the Slatino site, Sofia (researcher V. Nikolov; photo D. Radev) 357