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- Dead Sea Scrolls (4)
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Organisationseinheit der BAM
A combination of 3D micro X-ray fluorescence spectroscopy (3D micro-XRF) and micro-XRF was utilized for the investigation of a small collection of highly heterogeneous, partly degraded Dead Sea Scroll parchment samples from known excavation sites. The quantitative combination of the two techniques proves to be suitable for the identification of reliable marker elements which may be used for classification and provenance studies. With 3D micro-XRF, the three-dimensional nature, i.e. the depth-resolved elemental composition as well as density variations, of the samples was investigated and bromine could be identified as a suitable marker element. It is shown through a comparison of quantitative and semiquantitative values for the bromine content derived using both techniques that, for elements which are homogeneously distributed in the sample matrix, quantification with micro-XRF using a one-layer model is feasible. Thus, the possibility for routine provenance studies using portable micro-XRF instrumentation on a vast amount of samples, even on site, is obtained through this work.
Parchment has been in use for thousands of years
and has been used as the writing or drawing support for
many important historic works. A variety of analytical
techniques is currently used for routine assessment of the
degree of denaturation of historic parchment; however,
because parchment has a heterogeneous nature, analytical
methods with high spatial resolution are desirable. In this
work, the use of small-angle X-ray scattering (SAXS) and
synchrotron-IR (SR-IR) was examined in conjunction with
multivariate data analysis to study degradation of an
extended set of historic parchment samples, and particularly
to investigate the effect of lipids and the presence of iron
gall ink on the degradation processes. In the data analysis,
shrinkage temperature, lipid content, sample age, presence
of ink and accelerated degradation were included. The
analysis of loading factors in partial least-squares regression
and principal component analyses based on SAXS, SR-IR
and other analytical and descriptive data reveals the effect
of lipid removal on diffraction patterns, and lipids are found
to cause the degradation process in parchment to accelerate.
The effect of iron gall ink is also evident, although the
mechanism of ageing is different to that of natural ageing in
the absence of ink. In addition, a historic parchment score
from ca. 1750 is examined, demonstrating the significant
effect of iron gall ink, and lipids and inorganic soiling on its
increased degradation.
Unilateral and solid-state nuclear magnetic resonance
(NMR) analyses were performed on a parchment
fragment of the Dead Sea Scroll (DSS). The analyzed
sample belongs to the collection of non-inscribed and
nontreated fragments of known archaeological provenance
from the John Rylands University Library in Manchester.
Therefore, it can be considered as original DSS material
free from any contamination related to the post-discovery
period. Considering the paramount significance of the DSS,
noninvasive approaches and portable in situ nondestructive
methods are of fundamental importance for the determination
of composition, structure, and chemicalphysical
properties of the materials under study. NMR studies
reveal low amounts of water content associated with
very short proton relaxation times, T1, indicating a high
level of deterioration of collagen molecules within scroll
fragments. In addition, 13C cross-polarization magicangle-
spinning (CPMAS) NMR spectroscopy shows characteristic
peaks of lipids whose presence we attribute to
the production technology that did not involve liming.
Extraction with chloroform led to the reduction of both
lipid and protein signals in the 13C CPMAS spectrum
indicating probable involvement of lipids in parchment
degradation processes. NMR absorption and relaxation
measurements provide nondestructive, discriminative, and
sensitive tools for studying the deterioration effects on the
organization and properties of water and collagen within
ancient manuscripts.
In this work, we applied scanning electron
microscopy (SEM), microanalysis and Raman spectroscopy
to study the fungi inhabiting a richly illuminated parchment
document and the damage induced by their activity. To that
aim, we collected samples of fungal mycelium from the
deteriorated areas on a removable adhesive tape specifically
intended for lifting fungi without damaging the support.
SEM analysis of the adhesive tape samples showed the cooccurrence
of several species of fungi. One strain closely
resembling Acremonium species was observed only in the
tape micrographs but no agar cultures were obtained. Its
fungal structures showed the production of abundant
oxalates with an outstanding leaching of the calciumbased
materials of parchment (typically manufactured with
gypsum and lime). Needle-like crystals of calcium oxalate
produced by the fungus forming a uniform and quite
regular grid around conidial slimy heads were documented.
As a result, the areas affected by moulds were weakened,
stained and characterised by a powdery patina rich in
calcium. Confocal µ-Raman confirmed the presence of
oxalates while EDS showed the presence of calcium in
crystals. We conclude that the defacement of the parchment
was due to both collagenolytic activity, and to the
biotransformation of calcium-based minerals by fungi.
The aim of the research project 'Typology of
Dutch Drawing' was to establish an interdisciplinary approach
for investigating heterogeneous drawing collections.
To define a type common to a group of drawings, we
determine elements that are common to them based on style
and the use of identical materials. To that end, we investigated
about 750 Dutch drawings from the sixteenth century at the
Dresden Kupferstich-Kabinett using art historical and
scientific methods. In this work, we present a detailed
analysis of 30 drawings ascribed to the Egmont Master.
In this study, we address the question of the
provenance and origin of the Dead Sea Scrolls manuscripts.
A characteristic low ratio of chlorine to bromine, corresponding
to that of the Dead Sea water, may serve as an indicator for
local production. For this aim we developed a non-destructive
procedure to determine the Cl/Br ratio in the parchment of
these manuscripts. Micro-X-ray fluorescence (µ-XRF) measurements
of a large number of parchment and leather
fragments from the Dead Sea Scrolls were analyzed with a
routine we developed based on fundamental parameter
quantification. This routine takes into account the absorption
of the collagen matrix and the influence of the different sample
thicknesses. To calculate the representative Cl/Br ratio for each
fragment, we investigated the lateral homogeneity and
determined the total mass deposition using the intensity of
the inelastically scattered, characteristic tube radiation. The
distribution of the Cl/Br ratios thus obtained from the µ-XRF
measurements make it possible to distinguish fragments
whose origin lies within the Dead Sea region from those
produced in other locations.
The Dead Sea Scrolls that miraculously survived for over two thousand years suffered considerable damage due to various post-dicovery interventions. Today they are subjected to frequent travelling exhibitions. The current work collates the published information on exhibitions and conservational treatments with the results of the analytic studies of the skin-based material of the scrolls conducted since their discovery. The examination of the properties of the scrolls proves that frequent travel, exhibitons and the associated handling induce collagen deterioration that is covered up by the absence of a proper monitoring program.
Censorship of parts of written text was and is a common practice in totalitarian regimes. It is used to destroy information not approved by the political power. Recovering the censored text is of interest for historical studies of the text. This paper raises the question, whether a censored postcard from 1942 can be made legible by applying multispectral imaging in combination with laser cleaning. In the fields of art conservation (e.g. color measurements), investigation (e.g. Analysis of underdrawings in paintings), and historical document analysis, multispectral imaging techniques have been applied successfully to give visibility to information hidden to the human eye.
The basic principle of laser cleaning is to transfer laser pulse energy to a contamination layer by an absorption process that leads to heating and evaporation of the layer. Partial laser cleaning of postcards is possible; dirt on the surface can be removed and the obscured pictures and writings made visible again. We applied both techniques to the postcard. The text could not be restored since the original ink seems to have suffered severe chemical damage.
For many years after the discovery of the Dead Sea Scrolls, text analysis and fragment attribution were the main concern of the scholars dealing with them. The uncertain archaeological provenance of a large part of the collection added difficulties to the already formidable task of sorting thousands of fragments. After 60 years of scholarly research the questions of origin, archaeological provenance and correct attribution of the fragments are still debated. To help address these questions we have developed a methodology suitable for the material studies of the scrolls using combinations of X-ray, FTIR and Raman techniques. On the one hand, an accurate characterization of the highly heterogeneous writing media of the Dead Sea Scrolls leads to a reliable reconstruction of their history and, thus, contributes significantly to the current debate. On the other hand, it provides new information on the production of ancient parchment towards the end of the Second Temple period, opening a new page in the historical study of technology.
Quantifying degradation of collagen in ancient manuscripts: the case of the Dead Sea Temple Scroll
(2013)
Since their discovery in the late 1940s, the Dead Sea Scrolls, some 900 ancient Jewish texts, have never stopped attracting the attention of scholars and the broad public alike, because they were created towards the end of the Second Temple period and the 'time of Christ'. Most of the work on them has been dedicated to the information contained in the scrolls' text, leaving physical aspects of the writing materials unexamined. They are, however, crucial for both historical insight and preservation of the scrolls. Although scientific analysis requires handling, it is essential to establish the state of degradation of these valued documents. Polarized Raman Spectroscopy (PRS) is a powerful tool for obtaining information on both the composition and the level of disorder of molecular units. In this study, we developed a non-invasive and non-destructive methodology that allows a quantification of the disorder (that can be related to the degradation) of protein molecular units in collagen fibers. Not restricted to collagen, this method can be applied also to other protein-based fibrous materials such as ancient silk, wool or hair. We used PRS to quantify the degradation of the collagen fibers in a number of fragments of the Temple Scroll (11Q19a). We found that collagen fibers degrade heterogeneously, with the ones on the surface more degraded than those in the core.