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μ-PIXE mapping of archeological glazed pottery from Egypt
Applied Surface Science 332 (2015) 281–286
Contents lists available at ScienceDirect
Applied Surface Science journal homepage: www.elsevier.com/locate/apsusc
-PIXE mapping of archeological glazed pottery from Egypt H. Sadek ∗ Conservation Department, Faculty of Archaeology, Fayoum University, Egypt
a r t i c l e
i n f o
Article history: Received 14 November 2014 Received in revised form 2 January 2015 Accepted 18 January 2015 Available online 24 January 2015 Keywords: -PIXE Glaze Deterioration Fustat Mapping
a b s t r a c t -PIXE has been successfully applied in analysis of archaeological materials, it has many advantages. In this work -PIXE used in analysis of ancient Egyptian glazed pottery from Al-Fustat excavation repository have been chosen to represent different chemical compositions (fluxes and colorants) of glaze depending on its color. The chemical compositions with deterioration factors (humidity and temperature) worked together to make chemical changes on the surface of glaze. © 2015 Elsevier B.V. All rights reserved.
1. Introduction Ion Beam Analysis techniques use a high energetic beam of accelerated particles to study the composition of samples surfaces, IBA involves irradiation of samples by a beam of ions and the detection of one or more types of emitted radiation or particles that convey information about the samples compositions. There are two levels of energy used in IBA analysis, first at low energies (1–10 keV), O, Ne, or other heavy ion beams may be scattered from surface atoms or may cause removal of neutral, ionized, or excited atoms from the surface layer. Second, at high energies (>100 keV) proton, alpha, or heavier ions scatter from the nuclei of sample atoms or cause X-ray, ␥-ray, ion, or neutron emission from interactions or even sample atom recoil at depths of up to many micrometers [1]. -PIXE is a powerful tool for analysis of archaeological materials that gives information about the elemental composition of a material, -PIXE has multiple advantages (i) non-destructive, there is no visible damage because of sampling limitations, (ii) fast that large numbers of samples and positions can be measured in short time, (iii) versatile that with the same technique allow average compositional information to be obtained, elemental analysis or mapping for homogeneous and heterogeneous materials (iv)
∗ Tel.: +20 1063966161. E-mail address: [email protected] http://dx.doi.org/10.1016/j.apsusc.2015.01.115 0169-4332/© 2015 Elsevier B.V. All rights reserved.
multi-elemental by single measurement information on many elements obtained simultaneously [2]. Glazed pottery was made of mixture of natural materials, formed into shape, dried and finally transformed by heat to create a solid and stable material. Glaze layer is the thin coating of the pottery body; the glaze is based on a silicate (SiO4 ) network, with various compounds interspersed throughout this network in various patterns of concentration and distribution. Glaze is formed from silica-based, and the fusion of silica at low temperatures (700–800 ◦ C) is produced by adding flux, it charged with coloring agents to give homogeneous color to the pottery surfaces [3]. Various techniques were used for identification of the chemical compositions of archaeological pottery from Egypt; these techniques were used mainly for the study of pottery body while fewer studies were done on the glaze layer, although the glaze layer is important source of valuable information [4]. The chemical compositions of glaze provide archaeologists, curators and conservators with information’s about raw materials, colorants of the glaze and production technology. Chemical composition can used for dating of pottery objects [5]. The chemical compositions of the glaze play fatal role in deterioration process, however, weathering in the glaze layers attributed to a reaction between the glaze surface and aqueous solutions in contact environment in two stages process. First an ion exchange process between protonic species from the surface liquid and an alkali ion, which is removed from the glaze and results in the formation of an alkaline wet film on the surface, this film becomes increasingly alkaline.
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H. Sadek / Applied Surface Science 332 (2015) 281–286
Fig. 1. -PIXE elemental map of white glaze from Al-Fustat.
From year to year there is observed increasing role of IBA in study of cultural materials, for this is work -PIXE chosen as a power method because of the above advantages we used it to study the chemical compositions of glaze coloration and fluxes and contributions of elements in the glaze surface also, analyses of the morphological and chemical changes of the glass surfaces during the corrosion processes [6].
2. Experimental work 2.1. Sampling Twenty one fragments of glazed pottery were chosen for this study, the samples have different colors: white, black, yellow, brown, green, and blue, the samples are come from Al-Fustat. Al-Fustat is the name of the first Islamic capital of Egypt, established after the Islamic conquest of Egypt in 641A.C. Al-Fustat was an important production center of ceramics [7].
2.2. Instrumentation 2.2.1. Optical microscopy Axiotron Zeiss Optical Microscopes in Institute of Electronic Materials Technology (ITME) in Warsaw, Poland and Forschungs zentrum Dresden (FZD) used to visualize the glaze surface. Direct observations were done to the shards surfaces. 2.2.2. -PIXE analysis -PIXE analysis and mapping allows identification of compositions elements, the size of elemental scanned maps is an area of 2 mm square with diameter of beam 1 m, the samples holder is moved through the beam by means of the motorized stage (in the XYZ directions) A proton beam of 3.05 MeV from the 3 MV Tandetron accelerators at FZD (Forschungs zentrum Dresden, Germany). An Ortec Si (Li) detector was located outside the chamber behind a 125 m thick are windows allowing detection of characteristic Xrays for elements heavier than Na, to get an elemental map of the surface an optical microscope equipped with a CCD camera used to select the region of interest, the beam diameter 5 m size was scanned across the selected area usually 105 × 105 m [5,8].
H. Sadek / Applied Surface Science 332 (2015) 281–286
283
Fig. 2. Elemental distribution map of yellow glaze (Ca, Pb, K, Sn, Si, Sb, Fe, Cu and Mn). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
3. Results and discussion
3.3. Brown
The elemental compositions of glaze samples were determined, however, results and observations presented in this paper relate to major and minor elements content and its effect in glaze and deterioration patterns of the glaze surfaces.
The brown samples are lead glazes, in which the potassium is found at trace level. In these samples Fe acts as the main colorant agent, however, the hue varying from olive to brown is an effect of different ratio in Fe, Mn, Cu concentrations in addition to firing atmosphere.
3.1. White and colorless glaze The results obtained from IBA analysis of colorless and white glazes show that mixture of lead-alkaline was used as flux in the analyzed samples. Particles of cassiterite SnO2 used for opacification purpose were detected in the glaze in homogenous distribution as shown in Fig. 1. Impurities of Fe and Mn were identified by PIXE analysis carried on the selected samples; both Fe and Mn were responsible for giving to this white glaze the observed yellowish areas in the glaze.
3.2. Black Lead-alkaline glaze reported, however, with varying concentration of Pb and K. This glaze is colored by Mn and Fe oxides, these oxides are added to the glaze mixture intentional to get black glaze, that optical microscope did not shows any underlying black pigments that could alternative source of black glaze.
3.4. Yellow Lead-alkaline glaze containing a high amount of Pb with mixture of K and Ca was identified. In the -PIXE maps cassiterite SnO2 identified as the opacifier agent. Lead antimony Pb2 Sb2 O7 also identified in the yellow glazes, it comes from adding Sb2 O5 to lead oxides in the glaze compositions mixture, this mixture to the colorless glaze gives the yellow appearance. From the previous compositions of lead–antimony–tin with silica, the technology of anime (semifinished crystalline product) used as opaque pigment in glass can be considered. This technique of opacity and coloring of various shades, from yellow to orange caused by crystals of lead antimonite. Then it cooled and transformed to powder and added to transparent, colorless or colored glaze [9]. In yellow glazes Fe also appears as the minor content, Fig. 2.
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H. Sadek / Applied Surface Science 332 (2015) 281–286
Fig. 3. -PIXE map of homogenous blue glaze. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
3.5. Green The elemental compositions obtained from IBA analysis shows that lead were used as flux in the studied samples, the source of green color is due to presence of Cu and Fe, they used when glaze have a considerable amount of lead produce variations of green glaze [10]. 3.6. Blue There are mainly three degrees of blue glaze, light blue that use cobalt oxide as colorant, dark blue and finally the blue–green glaze (turquoise blue), -PIXE stated that lead-alkaline oxides were used, both Fe and Cu used to produces variations of blue from the -PIXE Fig. 3 it is the most homogenous composition and distribution of elements. According to [5] the blue glaze is in similar compositions to Egyptian blue (CaCuSi4 O10 ) which is synthetic pigment used in ancient Egyptian painting. 3.7. Deterioration Generally glaze is an inactive material, but according to surrounding environmental conditions such as relative humidity and temperature, physio-chemical changes in the glaze surface
compositions layer take place. Leached elements form a thin layer on the glaze surface and in advanced steps crust of corrosion will cover the original glaze. Discrimination by optical microscopy observations between deteriorated and non-deteriorated samples was made [11]. IBA used for comparison between chemical composition of non-deteriorated and deteriorated parts of glaze layer, -PIXE maps of non-deteriorated glaze shows that the elements distributions are homogenous Fig. 4a; on the other hand Ca which is a stabilizer against deteriorations processes in the glaze shows the low concentration. The immigration of elemental compositions from glaze matrix to the surface noticed in Fig. 4b. Despite Ca is stabilizer in the glaze, it found in higher concentration in the deteriorated parts than in the non-deteriorated due to the immigration to the surface, from the all analyzed deteriorated samples; there are different deterioration rates which were found low in the less alkaline glazes with higher stabilizer elements and high deterioration rate in high alkaline glaze with low stabilizer elements, this state that high content of stabilizer elements does not stop deterioration in presence of degradation factors such as humidity but can reduce the deterioration rate, therefore the degradation process stands on the two factors together, the chemical compositions factor and the environmental conditions.
H. Sadek / Applied Surface Science 332 (2015) 281–286
Fig. 4. -PIXE maps of glaze (a) non-deteriorated (b) deteriorated.
285
286
H. Sadek / Applied Surface Science 332 (2015) 281–286
4. Conclusion
References
Elemental contributions in the glaze were stated, the obtained results by -PIXE indicates that Egyptian potter’s in Al-Fustat used natural available pigments such iron, copper, lead oxides, . . ., etc., the craftsmen worked on the technology to get his requirements of colored glaze, concentration of raw materials, firing conditions (reduction or oxidation) and finally duration of firing. In the case of deterioration phenomena studies, it became clear that sometimes before any visual changes, the elemental composition change take place on the surface of glaze affected with deterioration. These means, that knowledge about the outermost and, separately, subsequent layers composition of historical glaze can help us to indicate that some processes occur. With this information we can be able to prevent further changes in such an object, using appropriate preservation and restoration treatment to save the precious culture heritage object.
[1] D.D. Cohen, R. Bird, N. Dytlewski, R. Siegele, Ion Beams for Materials Analysis, Encyclopedia of Physical Science and Technology, Academic Press, 2001. [2] Ch. Lahanier, G. Amsel, Ch. Heitz, M. Menu, H.H. Andersen, Nucl. Instrum. Methods Phys. Res. B 14 (1986) 1. [3] P.M. Rice, Pottery Analysis: A Sourcebook, University of Chicago Press, Chicago, 1987. [4] D.V. HILL, Chemical and mineralogical characterization of sasanian and early Islamic Glazed ceramics from Deh Luran Plain, Southweastern Iran, Archaeometry 46 (4) (2004) 585–605. [5] H. Sadek, et al., Identification of porcelain pigments by laser induced breakdown spectroscopy, J. Optoelectron. Adv. Mater. 14 (September–October (9–10)) (2012) 858–862. [6] B. Giussani, D. Monticelli, L. Rampazzi, Role of laser ablation-inductively coupled plasma-mass spectrometry in cultural heritage research: a review, Anal. Chim. Acta 635 (2009) 6–21. [7] R.B. Mason, K. Edward, Petrography of Islamic pottery from Fustat, J. Am. Res. Center in Egypt (1990) 165–183. [8] S. Abd El Aal, et al., Ion beam analysis of ancient Egyptian wall paintings, Vacuum 83 (2009) S4–S8. [9] M. Verità, et al., Glossary of Mosaic Glass Terms, Centre for Byzantine Cultural History, University of Sussex, Falmer, UK, 2009. [10] H. Sadek, Study of Technology, Treatment and Conservation of Archaeological Islamic Ceramic Lamps with Application on Some Selected Objects (M.Sc. thesis), Faculty of Archaeology, Cairo University, 2005. [11] S. Davison, Conservation and Restoration of Glass, 2nd ed., ButterworthHeinemann, UK, 2006.
Acknowledgments The author gratefully acknowledges the Research Centre Rossendorf Germany were supported by the European Community FMGE-CT98-0146 (Large Scale Facility AIM Rossendorf) Dr. Frans Munnik and A. Stonert and Prof. A. Turos from Soltan Institute of Nuclear Studies, Warsaw, Poland.
Contents lists available at ScienceDirect
Applied Surface Science journal homepage: www.elsevier.com/locate/apsusc
-PIXE mapping of archeological glazed pottery from Egypt H. Sadek ∗ Conservation Department, Faculty of Archaeology, Fayoum University, Egypt
a r t i c l e
i n f o
Article history: Received 14 November 2014 Received in revised form 2 January 2015 Accepted 18 January 2015 Available online 24 January 2015 Keywords: -PIXE Glaze Deterioration Fustat Mapping
a b s t r a c t -PIXE has been successfully applied in analysis of archaeological materials, it has many advantages. In this work -PIXE used in analysis of ancient Egyptian glazed pottery from Al-Fustat excavation repository have been chosen to represent different chemical compositions (fluxes and colorants) of glaze depending on its color. The chemical compositions with deterioration factors (humidity and temperature) worked together to make chemical changes on the surface of glaze. © 2015 Elsevier B.V. All rights reserved.
1. Introduction Ion Beam Analysis techniques use a high energetic beam of accelerated particles to study the composition of samples surfaces, IBA involves irradiation of samples by a beam of ions and the detection of one or more types of emitted radiation or particles that convey information about the samples compositions. There are two levels of energy used in IBA analysis, first at low energies (1–10 keV), O, Ne, or other heavy ion beams may be scattered from surface atoms or may cause removal of neutral, ionized, or excited atoms from the surface layer. Second, at high energies (>100 keV) proton, alpha, or heavier ions scatter from the nuclei of sample atoms or cause X-ray, ␥-ray, ion, or neutron emission from interactions or even sample atom recoil at depths of up to many micrometers [1]. -PIXE is a powerful tool for analysis of archaeological materials that gives information about the elemental composition of a material, -PIXE has multiple advantages (i) non-destructive, there is no visible damage because of sampling limitations, (ii) fast that large numbers of samples and positions can be measured in short time, (iii) versatile that with the same technique allow average compositional information to be obtained, elemental analysis or mapping for homogeneous and heterogeneous materials (iv)
∗ Tel.: +20 1063966161. E-mail address: [email protected] http://dx.doi.org/10.1016/j.apsusc.2015.01.115 0169-4332/© 2015 Elsevier B.V. All rights reserved.
multi-elemental by single measurement information on many elements obtained simultaneously [2]. Glazed pottery was made of mixture of natural materials, formed into shape, dried and finally transformed by heat to create a solid and stable material. Glaze layer is the thin coating of the pottery body; the glaze is based on a silicate (SiO4 ) network, with various compounds interspersed throughout this network in various patterns of concentration and distribution. Glaze is formed from silica-based, and the fusion of silica at low temperatures (700–800 ◦ C) is produced by adding flux, it charged with coloring agents to give homogeneous color to the pottery surfaces [3]. Various techniques were used for identification of the chemical compositions of archaeological pottery from Egypt; these techniques were used mainly for the study of pottery body while fewer studies were done on the glaze layer, although the glaze layer is important source of valuable information [4]. The chemical compositions of glaze provide archaeologists, curators and conservators with information’s about raw materials, colorants of the glaze and production technology. Chemical composition can used for dating of pottery objects [5]. The chemical compositions of the glaze play fatal role in deterioration process, however, weathering in the glaze layers attributed to a reaction between the glaze surface and aqueous solutions in contact environment in two stages process. First an ion exchange process between protonic species from the surface liquid and an alkali ion, which is removed from the glaze and results in the formation of an alkaline wet film on the surface, this film becomes increasingly alkaline.
282
H. Sadek / Applied Surface Science 332 (2015) 281–286
Fig. 1. -PIXE elemental map of white glaze from Al-Fustat.
From year to year there is observed increasing role of IBA in study of cultural materials, for this is work -PIXE chosen as a power method because of the above advantages we used it to study the chemical compositions of glaze coloration and fluxes and contributions of elements in the glaze surface also, analyses of the morphological and chemical changes of the glass surfaces during the corrosion processes [6].
2. Experimental work 2.1. Sampling Twenty one fragments of glazed pottery were chosen for this study, the samples have different colors: white, black, yellow, brown, green, and blue, the samples are come from Al-Fustat. Al-Fustat is the name of the first Islamic capital of Egypt, established after the Islamic conquest of Egypt in 641A.C. Al-Fustat was an important production center of ceramics [7].
2.2. Instrumentation 2.2.1. Optical microscopy Axiotron Zeiss Optical Microscopes in Institute of Electronic Materials Technology (ITME) in Warsaw, Poland and Forschungs zentrum Dresden (FZD) used to visualize the glaze surface. Direct observations were done to the shards surfaces. 2.2.2. -PIXE analysis -PIXE analysis and mapping allows identification of compositions elements, the size of elemental scanned maps is an area of 2 mm square with diameter of beam 1 m, the samples holder is moved through the beam by means of the motorized stage (in the XYZ directions) A proton beam of 3.05 MeV from the 3 MV Tandetron accelerators at FZD (Forschungs zentrum Dresden, Germany). An Ortec Si (Li) detector was located outside the chamber behind a 125 m thick are windows allowing detection of characteristic Xrays for elements heavier than Na, to get an elemental map of the surface an optical microscope equipped with a CCD camera used to select the region of interest, the beam diameter 5 m size was scanned across the selected area usually 105 × 105 m [5,8].
H. Sadek / Applied Surface Science 332 (2015) 281–286
283
Fig. 2. Elemental distribution map of yellow glaze (Ca, Pb, K, Sn, Si, Sb, Fe, Cu and Mn). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
3. Results and discussion
3.3. Brown
The elemental compositions of glaze samples were determined, however, results and observations presented in this paper relate to major and minor elements content and its effect in glaze and deterioration patterns of the glaze surfaces.
The brown samples are lead glazes, in which the potassium is found at trace level. In these samples Fe acts as the main colorant agent, however, the hue varying from olive to brown is an effect of different ratio in Fe, Mn, Cu concentrations in addition to firing atmosphere.
3.1. White and colorless glaze The results obtained from IBA analysis of colorless and white glazes show that mixture of lead-alkaline was used as flux in the analyzed samples. Particles of cassiterite SnO2 used for opacification purpose were detected in the glaze in homogenous distribution as shown in Fig. 1. Impurities of Fe and Mn were identified by PIXE analysis carried on the selected samples; both Fe and Mn were responsible for giving to this white glaze the observed yellowish areas in the glaze.
3.2. Black Lead-alkaline glaze reported, however, with varying concentration of Pb and K. This glaze is colored by Mn and Fe oxides, these oxides are added to the glaze mixture intentional to get black glaze, that optical microscope did not shows any underlying black pigments that could alternative source of black glaze.
3.4. Yellow Lead-alkaline glaze containing a high amount of Pb with mixture of K and Ca was identified. In the -PIXE maps cassiterite SnO2 identified as the opacifier agent. Lead antimony Pb2 Sb2 O7 also identified in the yellow glazes, it comes from adding Sb2 O5 to lead oxides in the glaze compositions mixture, this mixture to the colorless glaze gives the yellow appearance. From the previous compositions of lead–antimony–tin with silica, the technology of anime (semifinished crystalline product) used as opaque pigment in glass can be considered. This technique of opacity and coloring of various shades, from yellow to orange caused by crystals of lead antimonite. Then it cooled and transformed to powder and added to transparent, colorless or colored glaze [9]. In yellow glazes Fe also appears as the minor content, Fig. 2.
284
H. Sadek / Applied Surface Science 332 (2015) 281–286
Fig. 3. -PIXE map of homogenous blue glaze. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
3.5. Green The elemental compositions obtained from IBA analysis shows that lead were used as flux in the studied samples, the source of green color is due to presence of Cu and Fe, they used when glaze have a considerable amount of lead produce variations of green glaze [10]. 3.6. Blue There are mainly three degrees of blue glaze, light blue that use cobalt oxide as colorant, dark blue and finally the blue–green glaze (turquoise blue), -PIXE stated that lead-alkaline oxides were used, both Fe and Cu used to produces variations of blue from the -PIXE Fig. 3 it is the most homogenous composition and distribution of elements. According to [5] the blue glaze is in similar compositions to Egyptian blue (CaCuSi4 O10 ) which is synthetic pigment used in ancient Egyptian painting. 3.7. Deterioration Generally glaze is an inactive material, but according to surrounding environmental conditions such as relative humidity and temperature, physio-chemical changes in the glaze surface
compositions layer take place. Leached elements form a thin layer on the glaze surface and in advanced steps crust of corrosion will cover the original glaze. Discrimination by optical microscopy observations between deteriorated and non-deteriorated samples was made [11]. IBA used for comparison between chemical composition of non-deteriorated and deteriorated parts of glaze layer, -PIXE maps of non-deteriorated glaze shows that the elements distributions are homogenous Fig. 4a; on the other hand Ca which is a stabilizer against deteriorations processes in the glaze shows the low concentration. The immigration of elemental compositions from glaze matrix to the surface noticed in Fig. 4b. Despite Ca is stabilizer in the glaze, it found in higher concentration in the deteriorated parts than in the non-deteriorated due to the immigration to the surface, from the all analyzed deteriorated samples; there are different deterioration rates which were found low in the less alkaline glazes with higher stabilizer elements and high deterioration rate in high alkaline glaze with low stabilizer elements, this state that high content of stabilizer elements does not stop deterioration in presence of degradation factors such as humidity but can reduce the deterioration rate, therefore the degradation process stands on the two factors together, the chemical compositions factor and the environmental conditions.
H. Sadek / Applied Surface Science 332 (2015) 281–286
Fig. 4. -PIXE maps of glaze (a) non-deteriorated (b) deteriorated.
285
286
H. Sadek / Applied Surface Science 332 (2015) 281–286
4. Conclusion
References
Elemental contributions in the glaze were stated, the obtained results by -PIXE indicates that Egyptian potter’s in Al-Fustat used natural available pigments such iron, copper, lead oxides, . . ., etc., the craftsmen worked on the technology to get his requirements of colored glaze, concentration of raw materials, firing conditions (reduction or oxidation) and finally duration of firing. In the case of deterioration phenomena studies, it became clear that sometimes before any visual changes, the elemental composition change take place on the surface of glaze affected with deterioration. These means, that knowledge about the outermost and, separately, subsequent layers composition of historical glaze can help us to indicate that some processes occur. With this information we can be able to prevent further changes in such an object, using appropriate preservation and restoration treatment to save the precious culture heritage object.
[1] D.D. Cohen, R. Bird, N. Dytlewski, R. Siegele, Ion Beams for Materials Analysis, Encyclopedia of Physical Science and Technology, Academic Press, 2001. [2] Ch. Lahanier, G. Amsel, Ch. Heitz, M. Menu, H.H. Andersen, Nucl. Instrum. Methods Phys. Res. B 14 (1986) 1. [3] P.M. Rice, Pottery Analysis: A Sourcebook, University of Chicago Press, Chicago, 1987. [4] D.V. HILL, Chemical and mineralogical characterization of sasanian and early Islamic Glazed ceramics from Deh Luran Plain, Southweastern Iran, Archaeometry 46 (4) (2004) 585–605. [5] H. Sadek, et al., Identification of porcelain pigments by laser induced breakdown spectroscopy, J. Optoelectron. Adv. Mater. 14 (September–October (9–10)) (2012) 858–862. [6] B. Giussani, D. Monticelli, L. Rampazzi, Role of laser ablation-inductively coupled plasma-mass spectrometry in cultural heritage research: a review, Anal. Chim. Acta 635 (2009) 6–21. [7] R.B. Mason, K. Edward, Petrography of Islamic pottery from Fustat, J. Am. Res. Center in Egypt (1990) 165–183. [8] S. Abd El Aal, et al., Ion beam analysis of ancient Egyptian wall paintings, Vacuum 83 (2009) S4–S8. [9] M. Verità, et al., Glossary of Mosaic Glass Terms, Centre for Byzantine Cultural History, University of Sussex, Falmer, UK, 2009. [10] H. Sadek, Study of Technology, Treatment and Conservation of Archaeological Islamic Ceramic Lamps with Application on Some Selected Objects (M.Sc. thesis), Faculty of Archaeology, Cairo University, 2005. [11] S. Davison, Conservation and Restoration of Glass, 2nd ed., ButterworthHeinemann, UK, 2006.
Acknowledgments The author gratefully acknowledges the Research Centre Rossendorf Germany were supported by the European Community FMGE-CT98-0146 (Large Scale Facility AIM Rossendorf) Dr. Frans Munnik and A. Stonert and Prof. A. Turos from Soltan Institute of Nuclear Studies, Warsaw, Poland.