Analytische Chemie
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Eingeladener Vortrag
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The international Qumran project coordinated at the BAM, Berlin, resulted in an integrated methodology for determining the original and acquired properties of the skin-based writing surfaces of the Dead Sea Scrolls. This methodology offers a powerful tool for addressing such questions as the provenance, sorting and comparison of manuscripts. In addition, we have developed specific protocols for on-site studies, which were successfully applied to the fragments from the Schøyen collection in Norway. Our studies show that the Dead Sea Scrolls writing surfaces can be divided roughly into three groups: leather, parchments of a light tint, and those of various shades of brown. The latter ones are invariably tanned, whereas the middle group is characterized by the presence of various inorganic salts. Some of the pale parchments, among them the Temple Scroll (11Q19), are remarkably similar to medieval European parchment. Therefore we have formulated the working theory that in the Judaea of the Hellenistic period two different parchment-making traditions existed side by side: an ‘eastern’ one (represented by the tanned parchments of Qumran, closely resembling Aramaic documents from the fifth century BC, and a ‘western’ one (represented by the untanned/lightly tanned ones similar to early Christian Greek parchments).
This division has found support during our first pilot study of the Geniza fragments, in which Babylonian and Palestinian traditions seem to follow the “eastern” and “western” technologies, respectively.
The evolution and socio-geographic distribution of writing inks in late Antiquity and the early Middle Ages build the second focus of the BAM group. We use X-ray fluorescence analysis (XRF) to determine the chemical composition of the inks and NIR-reflectography for their typology. Here the early appearance of the metal containing inks clearly belongs to the western tradition as opposed to the continuous use of soot inks in the East.
The lecture will discuss the sensitive issue of authentication of the objects of cultural heritage of immense cultural and monetary value if certified to be genuine. It will be made clear that material analysis alone, especially its non-destructive variety conducted by specialists in a single technique, can not prove that the object is genuine. The best material analysis can do, after all appropriate tests have been conducted, is to announce that nothing has been found that contradicts the assumption of genuineness. Moreover, the results of the natural analysis can never be used as the only justification of the authentication in the cases of composite objects such as manuscripts or epigraphs. A certification always requires the expertise of the specialist in the field (be it a historian, paleographer, epigrapher, etc.), whose judgment can be at the most supported by appropriate material analysis.
The most effective approach for testing suspicious artifacts has been established by the forensic science. Here, not the authentication, but the determination of the forgery stands in the focus of the work. Investigation protocols developed within 150 years and constantly improved include a clear statement of the analysis purpose and the definition of plausibility criteria for the possible outcome. The younger sister of the forensics, archaeometry has to overcome additional obstacles such as the heterogeneity of historic material coupled with the scarcity of suitable reference material. Over the last two decades the popularity of archaeometric studies has increased enormously, with the industry-driven development of so-called non-destructive technologies (NDT) that do not require sampling. Further technological developments led to the appearance of NDT methods with extremely small interaction windows (µm range). Each of these methods has limitations that have to be carefully considered when planning the tests of a heterogeneous and often partially degraded historical material. This approach is inherently multi-instrumental, therefore archaeometric and forensic departments unite a number of specialists who work together defining the tasks and the methods involved for their successful completion.
The experimental knowledge about the inks of antiquity and late antiquity rarely goes beyond their visual description. In rare cases, inks typology has been determined by means of microscopy and reflectography, i.e. using their physical and optical properties, respectively. Soot, plant, and iron gall inks form different typological classes of historical black writing materials. Soot ink is a fine dispersion of carbon pigments in a water-soluble binding agent; plant-based ink consists of tannin solution; iron gall-ink presents a boundary case between soot and plant ink— a water soluble preliminary stage (similar to inks from the second group) oxidizes and evolves into a black, insoluble material (similar to the carbon pigments of the first group) when the writing is exposed to air. Each ink class has distinct properties that would readily permit their easy differentiation, if only these historical inks always belonged to just one of the classes above. In reality, inks may contain additives that obscure a clear picture.
All the black inks of the DSS have been hitherto identified as soot inks. Yet some manuscripts, with 1QapGen ar among them, display ink corrosion that is incompatible with the pure soot ink. This type of corrosion commonly observed in medieval manuscripts written with iron gall inks, results from the catalytic action of metallic component in the ink. Early analysis of this ink conducted by Nir El and Broshi in 1996 found copper in the corrosive inks and attributed its presence to the use of bronze inkwells. Re-investigation of the 1QapGen ar ink suggests, however, that the ink composition, soot + copper, agrees well with the ink recipe recorded in the 1st century CE by Dioscorides. Similar inks have been already attested on contemporary Egyptian papyri. The first part of the paper is dedicated to the new results on the inks and corrosion pattern of the 1QapGen ar.
In the second part of the presentation I will focus on the luxury scrolls, a distinct codicological type introduced by E. Tov. Our studies show that the preparation of the writing materials cannot supplement the list of codicological criteria offered by Tov. Therefore, one can divorce the writing material production from its inscription in contrast with the medieval scriptoria practices that included parchment production and copying of the manuscripts.
Material study of inks
(2016)
Our experimental knowledge about the inks of antiquity and late antiquity rarely goes beyond their visual description. In rare cases, inks typology has been determined by means of microscopy and reflectography, i.e. using their physical and optical properties, respectively. Soot, plant, and iron gall inks form different typological classes of historical black writing materials. Soot ink is a fine dispersion of carbon pigments in a water-soluble binding agent; plant-based ink consists of tannin solution; iron gall-ink presents a boundary case between soot and plant ink— a water soluble preliminary stage (similar to inks from the second group) oxidizes and evolves into a black, insoluble material (similar to the carbon pigments of the first group) when the writing is exposed to air. Each ink class has distinct properties that would readily permit their easy differentiation, if only these historical inks always belonged to just one of the classes above. In reality, inks may contain additives that obscure a clear picture.
Even crude observations suggest that the inks of antiquity differed greatly in their composition. We believe, that reconstructing the ink recipes with the help of advanced non-destructive analytical techniques could serve as a powerful accessory in the studies of ancient papyri.
The proposed paper will present a short survey of the methods of material analysis and the challenges offered by ancient inks. (Two) examples of ink studies from the collections of the Israel Museum in Jerusalem and Egyptian Museum in Berlin will conclude the paper.
Parchment
(2017)
This lecture will present history of parchment based on written sources and chemical examination of antique, medieval and modern parchment.
Our studies of the Dead Sea Scrolls writing surfaces show that they can be divided roughly into three groups: leather, parchments of a light tint, and those of various shades of brown. The latter ones are invariably tanned, whereas the middle group is characterized by the presence of various inorganic salts. Some of the pale parchments, among them the Temple Scroll (11Q19), are remarkably similar to medieval European parchment. Therefore we have formulated the working theory that in the Judaea of the Hellenistic period two different parchment-making traditions existed side by side: an ‘eastern’ one (represented by the tanned parchments of Qumran, closely resembling Aramaic documents from the fifth century BC, and a ‘western’ one (represented by the untanned/lightly tanned ones similar to early Christian Greek parchments).
This division has found support during our studies of the Geniza fragments, in which Babylonian and Palestinian traditions seem to follow the “eastern” and “western” technologies, respectively.
Investigation of physical properties and chemical composition of writing materials generates important data that we add to the results of the codicological analysis of the manuscripts. In its individual materiality, each manuscript is the result of a wide variety of influences. The “life” of a manuscript starts with its production that includes preparation of the writing surfaces and inks; it is followed by the use and storage, and finally characterized by treatment during restoration. Using instrumental analysis we record the characteristics that still exist. Combining our data with those obtained from the palaeographical and codicological analysis produces a new powerful tool for reconstruction of the history of a manuscript.
This paper addresses the role of material analysis in the current discussion on the authenticity of unprovenanced fragments. It will show that material analysis alone, especially its non-destructive variety, cannot prove that the object is genuine. The best material analysis can do, after all appropriate tests have been conducted, is to announce that nothing has been found that contradicts the assumption of genuineness. Moreover, the results of the material analysis can never be used as the only justification of authentication in cases of composite objects such as manuscripts or epigraphs.
The most effective approach for testing suspicious artifacts has been established by forensic science. Not limited to non-invasive analysis, this approach relies on validated techniques that usually require the extraction of samples and comparison with reference materials and are capable of delivering unambiguous results. In contrast, the analysis of suspicious manuscripts has to overcome additional obstacles such as the heterogeneity of historical material, the scarcity of suitable reference standards, and restriction to strictly non-invasive techniques.
We discuss the reliability of the testing protocol based on the non-destructive multi-instrumental approach developed by the BAM for the investigation of writing materials. In the case of the DSS, it relies on comparison with the genuine DSS fragments studied over the last 10 years.
This paper addresses the sensitive issue of authentication of the un-provenanced manuscripts of high monetary value if certified to be genuine.
Over the last decade the popularity of material studies of manuscripts using non-destructive technologies (NDT) has increased enormously. In the case of suspicious writings these studies are held in especially high esteem due to the methodological rigor they are reputed to contribute to debate. Moreover, audiences from a humanities background often tend to disregard the technical details and treat any published interpretation of instrumental analysis as an objective finding.
The paper will discuss the currently available methods and testing protocols for writing materials stressing the advantages and limitations of the non-invasive analysis. As an example we will consider the recent announcement of the possibility of non-invasive dating of carbon inks focusing on the validation required for a testing method.
We will make clear that material analysis alone cannot prove that the object is genuine. We should rather adopt the effective approach for testing suspicious artifacts that has been established by the forensic science. Here, not the authentication, but the determination of the forgery stands in the focus of the work.
The course presents panorama of historic writing inks, their use the methods of their identification. First, we discuss the possible types of the inks and show how one can determine these types using very simple instrumentation.
The change of the inks from those based on soot to the iron-gall inks commonly used in the Middle Age constitutes the second half of the course.
Material studies of inks
(2017)
The course presents panorama of historic writing inks, their use the methods of their identification. First, we discuss the possible types of the inks and show how one can determine these types using very simple instrumentation.
The change of the inks from those based on soot to the iron-gall inks commonly used in the Middle Age constitutes the second half of the course.