Maria Filomena Guerra
National Council for Scientific Research, Chemistry, Faculty Member
- Archaeometallurgy, Trade and Exchange, Archaeometry, Commerce and Market Exchange, Conflict, warfare, and relief, Ceramics, archeometry, Chemistry, Archaeology, Prehistoric Archaeology, and 9 moreMedieval History, Ancient Near East, Funerary Archaeology, Archaeometry, Bronze Age Europe (Archaeology), Archaeological Science, Archéologie, Early Bronze Age (Archaeology), and Iron Age Iberian Peninsula (Archaeology)edit
Forty-two mosaic coloured/opaque " glass " tesserae from three sites (Milan, Italy; Durrës, Albania; Hier-apolis, Turkey) situated in the Western and Eastern parts of the Roman/Byzantine Empire, dated between the 5th and the 9th... more
Forty-two mosaic coloured/opaque " glass " tesserae from three sites (Milan, Italy; Durrës, Albania; Hier-apolis, Turkey) situated in the Western and Eastern parts of the Roman/Byzantine Empire, dated between the 5th and the 9th centuries, were studied by optical microscopy, SEM-EDX and Raman micro-spectroscopy in order to investigate the nature of their pigments and opacifiers as well as the micro-structure of glass ceramic materials. The Raman signatures of glass matrix and phases dispersed in the soda-lime glassy matrix showed the presence of six opacifiers/pigments. The use of soda ash glass in the tesserae from Durrës (post 8th c.) allows refining the mosaic debated chronology. The use of soda ash matrix glass together with the presence of calcium antimonates (Ca 2 Sb 2 O 7 and CaSb 2 O 6), pyrochlore solid solution/Naples' yellow (PbSb 2 À x À y Sn x M y O 7 À δ) and cuprite (Cu 2 O) or metallic copper (Cu 0) in many samples show the technological continuity in a Roman tradition. However, the presence of cas-siterite (SnO 2) and quartz (SiO 2) in one sample from the beginning of the 5th century, diverging from Roman technology, offers a chronological marker to identify newly (not re-used) produced tesserae.
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This paper presents a technological study of items of Egyptian jewellery from the collections of the National Museums Scotland: a pendant from the 19th century BC; objects from the 16th century BC royal burial unearthed at Qurneh; two... more
This paper presents a technological study of items of Egyptian jewellery from the collections of the National Museums Scotland: a pendant from the 19th century BC; objects from the 16th century BC royal burial unearthed at Qurneh; two gold finger-rings dated to the 14th century BC; and a group of pendants from the 13th century BC. The objects were examined using optical microscopy, X-radiography and Scanning Electron Microscopy (SEM). In addition, the elementary compositions of alloys and solder joints were investigated using air-path X-ray fluorescence (XRF), proton-induced X-ray analysis (micro-PIXE), and energy-dispersive X-ray analysis (SEM-EDS). This preliminary study provides information about the evolution of alloy composition and the use of alluvial gold, and illustrates the Ancient Egyptian goldsmiths’ skills in working with wires, granulation and joining techniques.
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El conocimiento actual de la orfebrería inca es limitado. A pesar de los descubrimientos esporádicos de piezas en contexto arqueológico, la gran mayoría de los objetos en oro y plata existentes provienen del proceso de saqueo y de... more
El conocimiento actual de la orfebrería inca es limitado. A pesar de los
descubrimientos esporádicos de piezas en contexto arqueológico, la gran mayoría de los objetos en oro y plata existentes provienen del proceso de saqueo y de destrucción de tumbas, templos y santuarios de altura, consecutivos a la conquista española, careciendo de documentación contextual.
descubrimientos esporádicos de piezas en contexto arqueológico, la gran mayoría de los objetos en oro y plata existentes provienen del proceso de saqueo y de destrucción de tumbas, templos y santuarios de altura, consecutivos a la conquista española, careciendo de documentación contextual.
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La orfebrería en los Andes en la época inca (siglos XV-XVI) Las estatuillas incas del musée du quai Branly-Jacques Chirac: variedad tipológica y cronología de las producciones Les figurines incas du musée du quai Branly-Jacques Chirac :... more
La orfebrería en los Andes en la época inca (siglos XV-XVI) Las estatuillas incas del musée du quai Branly-Jacques Chirac: variedad tipológica y cronología de las producciones Les figurines incas du musée du quai Branly-Jacques Chirac : variété typologique et chronologie des productions The Inca figurines of the musée du quai Branly-Jacques Chirac: typological variety and production chronology, « Las estatuillas incas del musée du quai Branly-Jacques Chirac: variedad tipológica y cronología de las producciones », Bulletin de l'Institut français d'études andines [En línea], 46 (1) | 2017, Publicado el 08 abril 2017, consultado el 04 enero 2018. URL : http://journals.openedition.org/bifea/8198 ; DOI : 10.4000/bifea.8198 Les contenus du Bulletin de l'Institut français d'études andines sont mis à disposition selon les termes de la licence Creative Commons Attribution-Pas d'Utilisation Commerciale-Pas de Modification 4.0 International.
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Fourteen hollow and one cast anthropomorphic and zoomorphic figurines produced in Incan times for ritual offerings from the Ethnologisches Museum in Berlin were selected to investigate the technologies and alloys used for their... more
Fourteen hollow and one cast anthropomorphic and zoomorphic figurines produced in Incan times for ritual offerings from the Ethnologisches Museum in Berlin were selected to investigate the technologies and alloys used for their fabrication with portable optical microscopy and non-destructive XRF elemental analysis. This group of gold and silver figurines includes typical specimens of the Inca production, such as the four silver figurines from the Island Coati in Lake Titicaca and the two gold figurines from Pachacamac, as well as specimens that are seldom present in collections, which makes them atypical. In addition to the tall figurines with atypical hair or standing pose, one bicolour figurine (half silver, half gold) and another with coloured inlays were included in this study for comparison. The large majority of the silver specimens are made from very high quality alloys and the gold figurines are made from alloys containing low copper contents and silver ranging from 30wt% to 52wt%.
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The hollow silver male miniature figurine from National Museums Scotland is one of the tallest specimens made in precious metals attributed to the Incas. In spite of showing the expected characteristics of this type of Inca production for... more
The hollow silver male miniature figurine from National Museums Scotland is one of the tallest specimens made in precious metals attributed to the Incas. In spite of showing the expected characteristics of this type of Inca production for ritual offerings —regular proportions and standing pose, representation of its gender, bulging cheek associated to coca leaves chewing and elongated earlobes— this figurine differs from the regular figurines by the form of the top of its head. In addition, the skilled decoration includes details such as well portrayed feet. The technologies and the alloy employed in its manufacture were examined using a stereo microscope and by non-destructive X-ray fluorescence analysis. Comparison between this figurine with the hollow silver male figurines of equivalent stature and typology kept at Dumbarton Oaks Research Library and Collection and Museum of America shows that they are all made with the same technology and by employing silver alloys with copper contents below 0.5%. These alloys are richer in silver than the majority of the alloys employed to fabricate normal Inca hollow figurines of known provenance or from other museum collections.
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The tupu, tupo or pin has been manufactured for more than 1700 years to embellish women’s clothing in the Andes. Women typically wore clothing pins, but archaeological evidencs shows that these pins were also used as part of the capacocha... more
The tupu, tupo or pin has been manufactured for more than 1700 years to embellish women’s clothing in the Andes. Women typically wore clothing pins, but archaeological evidencs shows that these pins were also used as part of the capacocha ceremonies and as an offering to the huacas. Depending on fashion and woman’s social status, tupus were made using different metals and alloys such as gold, silver, tumbaga, copper, bronze and brass. When taken out of context they are difficult to date. In our work we searched for the characteristics of the silver alloys used in their fabrication to check whether any criteria could be linked to their period of production, in particular for the miniature tupus from the capacocha silver figurines.
A group of silver tupus belonging to the Museo Inka of the Universidad Nacional de San Antonio Abad del Cusco, and to the Museo de Oro y Armas del Mundo of Lima were analyzed by X-ray fluorescence (XRF). A few capacocha silver figurines from the Museo de Oro y Armas del Mundo were included in this analytical study. Data obtained were compared to the composition of both silver coins struck in Potosi and the rare published tupus and figurines analysis.
A group of silver tupus belonging to the Museo Inka of the Universidad Nacional de San Antonio Abad del Cusco, and to the Museo de Oro y Armas del Mundo of Lima were analyzed by X-ray fluorescence (XRF). A few capacocha silver figurines from the Museo de Oro y Armas del Mundo were included in this analytical study. Data obtained were compared to the composition of both silver coins struck in Potosi and the rare published tupus and figurines analysis.
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Six figurines and seven miniature tupus from ritual sacrifices and offerings, made from silver alloys and gold alloys exist in the collection of the Museo Inka in Cusco (Peru). They are dated to the Inca period and were found in the... more
Six figurines and seven miniature tupus from ritual sacrifices and offerings, made from silver alloys and gold alloys exist in the collection of the Museo Inka in Cusco (Peru). They are dated to the Inca period and were found in the archaeological site of Chimur, in Chayllabamba, district of Paucartambo. In this article, we present a study of them by optical microscopy and mobile X-ray fluorescence spectrometry (pXRF). This group of objects includes the only known two-coloured anthropomorphic figurine (made from silver and from copper) with provenience. It also includes an undamaged offering consisting of a wood box containing a silver female figurine wrapped in a cloth fastened with two silver tupus. The research results obtained on the figurines’ typology and on the diversity of the technologies and alloys employed for their production are discussed, as well as the homogeneity of the tupus production.
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Habitants des hauts plateaux et des vallées inter-andines dans la cordillère colombienne avant la conquête espagnole, les Muiscas ont développé une culture et des pratiques religieuses où les offrandes votives occupent une large place.... more
Habitants des hauts plateaux et des vallées inter-andines dans la cordillère colombienne avant la conquête espagnole, les Muiscas ont développé une culture et des pratiques religieuses où les offrandes votives occupent une large place. L’étude approfondie des figurines muiscas (tunjos) de la collection du musée du quai Branly-Jacques Chirac a permis de préciser le degré de technicité des orfèvres de cette aire culturelle, qui maîtrisaient les alliages or-cuivre-argent comme la fonte à la cire perdue.
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The corrosion of copper and silver in sulphide environments was assessed by several analytical techniques to investigate the influence of each one on the corrosion of sterling silver. The surface colour changes with the immersion time due... more
The corrosion of copper and silver in sulphide environments was assessed by several analytical techniques to investigate the influence of each one on the corrosion of sterling silver. The surface colour changes with the immersion time due to the formation of corrosion products composed of particles with distinct sizes and shapes and the consequent layer thickening. Ag 2 S is the main corrosion product of silver. At early stages of corrosion, Cu develops Cu 2 O and Cu 2 S, and later Cu 2 O again. After the corrosion of sterling silver, pure Cu and Ag are compared, and the predominant influence of Cu at the first stages may be suggested whilst Ag mainly contributes to longer corrosion stages. The layer-by-layer corrosion structure observed for the sulphidation of sterling silver was not observed for its constituent elements.
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Sterling silver samples, prepared to simulate cultural heritage surfaces, were subjected to accelerated ageing tests through exposure to sulphide containing environments. Data obtained by X-ray diffraction, ultraviolet-visible... more
Sterling silver samples, prepared to simulate cultural heritage surfaces, were subjected to accelerated ageing tests through exposure to sulphide containing environments. Data obtained by X-ray diffraction, ultraviolet-visible spectrophotometry, contact angle goniometry, ellipsometry and scanning electron microscopy revealed, contrarily to what has been suggested, that the colour of corroded surfaces is related to the thickness of the corrosion layer and to the multi-layer structure of various corrosion products. At the early stages of corrosion, Cu prevails over the Ag compounds. In subsequent stages, AgCuS complexes were also detected. Ag 2 S is the prevailing corrosion product after longer periods of time.
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Patination has been frequently used by jewellers to modify the colour of silver alloys. By application of a solution of sulphur compounds, blackish or bluish surfaces can be obtained, but the intentionally produced silver-sulphur... more
Patination has been frequently used by jewellers to modify the colour of silver alloys. By application of a solution of sulphur compounds, blackish or bluish surfaces can be obtained, but the intentionally produced silver-sulphur compounds are chemically similar to the atmospheric corrosion products that develop on silver alloys. The conservation of patinated silver objects, such as Art Nouveau jewellery, raises thus analytical challenges. In order to define accurate conservation treatments, the patina and corroded surfaces characterisation is mandatory. In this study, sterling silver samples were patinated and subjected to corrosion by immersion in a sulphide containing solution. The identification of the chemical compounds present on the patinated sterling silver before and after corrosion was carried out by UV-visible spectrophotometry, X-ray diffraction and scanning electron microscopy with energy dispersive X-ray spectrometry. Data obtained suggest a two-stage corrosion process: a decrease of the silver compounds patina thickness caused by its dissolution, followed by the formation of corrosion products with different compositions and morphologies containing silver and copper sulphur compounds. * A quem a correspondência deve ser dirigida, e‐mail: isabel.ssot@archeofactu.pt
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Excavation of an intact burial at Haraga, Egypt (12th Dynasty) revealed the unusual presence of several gold catfish and tilapia pendants and gold bead necklaces , now in the collection of National Museums Scotland (NMS). Analysis of the... more
Excavation of an intact burial at Haraga, Egypt (12th Dynasty) revealed the unusual presence of several gold catfish and tilapia pendants and gold bead necklaces , now in the collection of National Museums Scotland (NMS). Analysis of the pendants and gold beads by XRF and PIXE/PIGE has shown that the majority were made from silver-rich electrum with quantities of silver between 20wt% and 40wt%. Only the most skilfully crafted fish pendant was made with a high-purity gold alloy containing less than 7wt% silver. The gold beads, which were made by rolling foils of different thicknesses on a lime plaster core, are highly degraded. FEG-SEM observation of one corroded fragment revealed a porous texture of the surface corresponding to a failed annealing that caused an increase of the corrosion rate. The surface of the beads has a red coloration caused by the formation of gold-silver-sulphur compounds, characteristic of atmospheric corrosion of gold-based alloys.
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Application of analytical techniques to the study of Portuguese and Brazilian coinages.
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Analysis of dinars and Visigothic coins by proton activation analusis and LA-ICP-MS.
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The gold jewellery collection exhibited in the Treasure Room of the National Archaeology Museum in Lisbon, Portugal, developed a severe surface corrosion. In order to approach the corrosion mechanisms, the state of conservation of the... more
The gold jewellery collection exhibited in the Treasure Room of the National Archaeology Museum in Lisbon, Portugal, developed a severe surface corrosion. In order to approach the corrosion mechanisms, the state of conservation of the objects and the exhibition conditions were characterised. The temperature, the relative air humidity and the light were measured. The pollutants and the exhibition materials of the showcases were identified. The relation between the exhibition conditions and the corrosion development was search.
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Excavation of an intact burial at Haraga, Egypt (12th Dynasty) revealed the unusual presence of several gold catfish and tilapia pendants and gold bead necklaces , now in the collection of National Museums Scotland (NMS). Analysis of the... more
Excavation of an intact burial at Haraga, Egypt (12th Dynasty) revealed the unusual presence of several gold catfish and tilapia pendants and gold bead necklaces , now in the collection of National Museums Scotland (NMS). Analysis of the pendants and gold beads by XRF and PIXE/PIGE has shown that the majority were made from silver-rich electrum with quantities of silver between 20wt% and 40wt%. Only the most skilfully crafted fish pendant was made with a high-purity gold alloy containing less than 7wt% silver. The gold beads, which were made by rolling foils of different thicknesses on a lime plaster core, are highly degraded. FEG-SEM observation of one corroded fragment revealed a porous texture of the surface corresponding to a failed annealing that caused an increase of the corrosion rate. The surface of the beads has a red coloration caused by the formation of gold-silver-sulphur compounds, characteristic of atmospheric corrosion of gold-based alloys.
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The corrosion of copper and silver in sulphide environments was assessed by several analytical techniques to investigate the influence of each one on the corrosion of sterling silver. The surface colour changes with the immersion time due... more
The corrosion of copper and silver in sulphide environments was assessed by several analytical techniques to investigate the influence of each one on the corrosion of sterling silver. The surface colour changes with the immersion time due to the formation of corrosion products composed of particles with distinct sizes and shapes and the consequent layer thickening. Ag 2 S is the main corrosion product of silver. At early stages of corrosion, Cu develops Cu 2 O and Cu 2 S, and later Cu 2 O again. After the corrosion of sterling silver, pure Cu and Ag are compared, and the predominant influence of Cu at the first stages may be suggested whilst Ag mainly contributes to longer corrosion stages. The layer-by-layer corrosion structure observed for the sulphidation of sterling silver was not observed for its constituent elements.
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To pay their soldiers, the Dutch issued in the 17th century obsidional coins inscribed “BRASIL” made from gold and silver. Five coins in the collection of the Museu Histórico Nacional in Rio de Janeiro were examined and analysed in this... more
To pay their soldiers, the Dutch issued in the 17th century obsidional coins inscribed “BRASIL” made from gold and silver.
Five coins in the collection of the Museu Histórico Nacional in Rio de Janeiro were examined and analysed in this work.
Five coins in the collection of the Museu Histórico Nacional in Rio de Janeiro were examined and analysed in this work.
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Analysis by XRF of the Bronze Age halberd of Atlantic type found at Baútas habitat
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Wisigothic and Suevian gold coins were analysed to search for the origin of the gold. Two gold supplies could be defined. The analysis of a group of dinares shows the use of recycling.
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Analysis by PIXE of the Danish coinage struck by King Harold Bluetooth and comparison with issues struck in the same period.
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The analysis by PIXE and PAA of 64 coins struck in Iron Age Armorica by the Osismi tribe revealed the use of a different system from the usual Celtic Gaul tri-metallic system. The gold-based alloy (Au–Ag–Cu) firstly issued is debased over... more
The analysis by PIXE and PAA of 64 coins struck in Iron Age Armorica by the Osismi tribe revealed the use of a different system from the usual Celtic Gaul tri-metallic system. The gold-based alloy (Au–Ag–Cu) firstly issued is debased over time to become a silver-based alloy (Ag–Cu–Sn). Based on the analytical data, two chronological phases were defined and dates of issuing could be ascribed to the coin-types. The presence of Sn and Sb in the alloys and the low contents of Pb were used in the attribution of 9 specimens of unknown origin to the Osismi monetary system. Considerations on the mints supplies could also be provided.
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Sterling silver samples, prepared to simulate cultural heritage surfaces, were subjected to accelerated ageing tests through exposure to sulphide containing environments. Data obtained by X-ray diffraction, ultraviolet-visible... more
Sterling silver samples, prepared to simulate cultural heritage surfaces, were subjected to accelerated ageing tests through exposure to sulphide containing environments. Data obtained by X-ray diffraction, ultraviolet-visible spectrophotometry, contact angle goniometry, ellipsometry and scanning electron microscopy revealed, contrarily to what has been suggested, that the colour of corroded surfaces is related to the thickness of the corrosion layer and to the multi-layer structure of various corrosion products. At the early stages of corrosion, Cu prevails over the Ag compounds. In subsequent stages, AgCuS complexes were also detected. Ag 2 S is the prevailing corrosion product after longer periods of time.
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Fifty-eight gold leaf tesserae from eight archaeological sites situated in the Byzantine Empire and two Early Islamic (one in medieval Palestine), covering the period that goes from the 4th c. to the 12th c., were analysed by EPMA,... more
Fifty-eight gold leaf tesserae from eight archaeological sites situated in the Byzantine Empire and two Early Islamic (one in medieval Palestine), covering the period that goes from the 4th c. to the 12th c., were analysed by EPMA, SEM-EDS and PIXE-PIGE to determine the composition of both the glass and the gold leaves. The good match until the 6th c. between circulating monetary alloys and the gold leaf compositions together with the type of glass used, provided criteria that can be used to date the tesserae fabrication. The data obtained allow newly produced tesserae to be distinguished from re-used ones. Because after the 7th c. the circulation of gold in the Byzantine Empire was less controlled, the same relationship is harder to establish. The results suggest the existence of workshops in the Eastern and Western part of the Mediterranean and a more advanced technology to manufacture a palette of glass colours for gold leaf tesserae in the Eastern region.
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Previous studies conducted on indigenous jewellery from Patagonia have focused on collections from Araucania (Centre-South of Chile), and to a smaller degree on the 19th-century silver production from the Eastern Andean cordillera. This... more
Previous studies conducted on indigenous jewellery from Patagonia have focused on collections from Araucania (Centre-South of Chile), and to a smaller degree on the 19th-century silver production from the Eastern Andean cordillera. This work presents the results obtained from the study of the silver earrings collected by Henry de La Vaulx in Valentín Saygüeque's camp (1830-1903). Saygüeque was a cacique (chief) renowned for the monetary and jewellery treasure he had accumulated prior to his military defeat of 1882, period during which he led a group of mixed huilliche, pehuenche, pampa and tehuelche origins who controlled the " País de las Manzanas " (the Land of Apples) (province of Neuquén, Argentina). The formal, technological and chemical analysis of the collection kept at the Musée du quai Branly in Paris offers a first summary of a geographically and chronologically contextualized silver production, and provides analytical criteria for the dating of native jewellery.
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The gold necklace and penannular earrings from tomb 296 at Riqqa, containing the coffins of a female and of a male, the latter a scribe named Beri of the reign of Tuthmosis III (eighteenth Dynasty Egypt), were analysed by PIXE, XRF, and... more
The gold necklace and penannular earrings from tomb 296 at Riqqa, containing the coffins of a female and of a male, the latter a scribe named Beri of the reign of Tuthmosis III (eighteenth Dynasty Egypt), were analysed by PIXE, XRF, and EDS, together with eight penannular earrings from other find-spots of the same period. Analysis of jewellery items from tomb 296 at Riqqa revealed the use of high-purity gold alloys and electrum alloys, while the other earrings investigated were found to be made of electrum with high Ag content. Two earrings conserved in different museums were shown to be originally a pair. PIXE mapping revealed the extensive use of a hard soldering technique for the joints, with the solders being obtained by the addition of Cu to the base alloy. The presence of PGE inclusions indicated the use of alluvial gold, but the variability of their composition could be ascribed to the recycling of gold from different origins, in the case of some objects.
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3D representations were made of a small Egyptian scarab with a gold band by a number of methods, based on photogrammetry and photometric stereo. They were evaluated for colour fidelity and spatial detail, in the context of a study of... more
3D representations were made of a small Egyptian scarab with a gold band by a number of methods, based on photogrammetry and photometric stereo. They were evaluated for colour fidelity and spatial detail, in the context of a study of toolmarks and manufacturing techniques of jewellery in ancient Egypt. It was found that although a 3D laser scanner gave the best geometric accuracy, the camera-based methods of photogrammetry and photometric stereo gave better representation of fine detail and colour on the object surface.
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Non-destructive elemental analysis and examination provided criteria to identify the pastiches and restorations in the Campana's collection of jewellery
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A group of Bronze Age and Iron Age gold torcs and earrings from the Iberian Atlantic façade, several with tarnishing, are studied with different X-ray-based techniques, including portable devices for in situ analysis. The construction of... more
A group of Bronze Age and Iron Age gold torcs and earrings from the Iberian Atlantic façade, several with tarnishing, are studied with different X-ray-based techniques, including portable devices for in situ analysis. The construction of the complex objects is discussed, and information on the evolution of the alloys is provided. By comparing the elemental composition of the analysed objects with published data for Bronze Age and Iron Age jewellery from the Portuguese area and with data obtained and published for Chalcolithic objects from the Iberian area, the changes in gold supplies could be discussed, and this has led to suggest changes in the chronological attribution of three torcs, on the reuse without melting of one pair of earrings and on the origin of the so-called gold ingots. The analysis of tarnished areas of the torcs and the earrings showed the presence of distinct corrosion products due to atmospheric corrosion, which could be in part identified
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A new irradiation device allowing a bulk non destructive neutron activation analysis of small archeological objects is applied to the study of Argentomagus fibulae. The change of alloy, from bronze to brass, at this site, for the... more
A new irradiation device allowing a bulk non destructive neutron activation analysis of small archeological objects is applied to the study of Argentomagus fibulae. The change of alloy, from bronze to brass, at this site, for the manufacture of fibulae is confirmed by our first results
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Different analytical methods are now available for researchers working on copper or copper alloy coins and objects. A comparison of three non-destructive ion beam techniques is presented: particle-induced X-ray emission (PIXE) using a van... more
Different analytical methods are now available for researchers working on copper or copper alloy coins and objects. A comparison of three non-destructive ion beam techniques is presented: particle-induced X-ray emission (PIXE) using a van de Graaff accelerator, proton activation analysis (PAA) and fast neutron activation analysis (FNAA) using a cyclotron.
In order to verify the accuracy and the precision of these three methods our experiment was first carried out on brass and bronze industrial standards and afterwards on five coins
described in table 1, with the following composition: one of copper, two of orichalcum and two of lead-bronze.
In order to verify the accuracy and the precision of these three methods our experiment was first carried out on brass and bronze industrial standards and afterwards on five coins
described in table 1, with the following composition: one of copper, two of orichalcum and two of lead-bronze.
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The problems concerning the study of the provenance of minted gold using classical analytical as well as the inductively coupled plasma mass spectrometry technique associated to a laser ablation are discussed. After the choice of the... more
The problems concerning the study of the provenance of minted gold using classical analytical as well as the inductively coupled plasma mass spectrometry technique associated to a laser ablation are discussed. After the choice of the parameters for a new laser of UV type, we consider questions like the reproducibility of the analysis and the limits of detection as well as the advantages of this technique compared to proton activation analysis.
The first results on the application of the LA-ICP-MS to the study of the 1 8th century minted gold in Europe and to the Phillips II stater copies in Gaul, estimate the possibilities of the technique to differentiate gold from different origins.
The first results on the application of the LA-ICP-MS to the study of the 1 8th century minted gold in Europe and to the Phillips II stater copies in Gaul, estimate the possibilities of the technique to differentiate gold from different origins.
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A análise de objetos arqueológicos e museológicos fornece informações preciosas sobre as técnicas de fabricação utilizadas pelos antigos artesãos, sobre os circuitos comerciais explorados pelos nossos antepassados e sobre o estado de... more
A análise de objetos arqueológicos e museológicos fornece informações preciosas sobre as técnicas de fabricação utilizadas pelos antigos artesãos, sobre os circuitos comerciais explorados pelos nossos antepassados e sobre o estado de conservação dos objetos.
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Resultados das análises dos materiais em bronze e latão exumados das 29 sepulturas da Necrópole de Talaíde (Cascais, Portugal)
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The first gold coin is attributed to Croesus (560-546) king of Lydia whose fabulous wealth created one of the most legendary characters of History. One century later Lydia became a province of the Persian Empire which spread from Asia... more
The first gold coin is attributed to Croesus (560-546) king of Lydia whose fabulous wealth created one of the most legendary characters of History. One century later Lydia became a province of the Persian Empire which spread from Asia Minor to the Indus and from Egypt to the Danube. The hanker after this empire rich in mining resources gave rise to one golden age in the Antiquity under Alexander the Great (356-323 BC) and another in the Middle Ages all over the Muslim conquest (660-750 AD). With the coupling of 12 MeV proton activation analysis with LA-ICP-MS we tried to characterise the gold used to strike the coinages made during those historical periods in order to study the debasement of the coins and the provenance of the ores. Only one coinage struck in the Antiquity presented a debasement: the double-darics attributed to the Babylonian mint. Using the concentration of the trace elements present in the metal we could check the re-use of Persian treasures to strike the Alexander's type staters and show the use of two types of gold in the Macedonian mints. For the Near and Middle Eastern Muslim dinars we could suggest the use of three different gold ores in their fabrication.
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A new PIXE setup at the external beamline of the AGLAE accelerator is assessed for fast mapping the joining regions and the PGE inclusions of nine Egyptian gold items from the Louvre museum collection, dated to the end of the Second... more
A new PIXE setup at the external beamline of the AGLAE accelerator is assessed for fast mapping the joining regions and the PGE inclusions of nine Egyptian gold items from the Louvre museum collection, dated to the end of the Second Intermediate Period and to the New Kingdom. The setup is composed of a cluster of SDD detectors divided in two “super detectors” dedicated to analyse the matrix and the trace elements. It provides the possibility to realise large and/or fast maps on artefacts by scanning of the beam over the sample surface. Different softwares have been developed or updated to visualise, process, and quantify the data.
By using this setup, we could determine the elemental distribution of major elements Au, Ag and Cu on the different joining regions, estimate the composition of the brazes, and show that they were produced by adding Cu to the base gold alloy. By fast mapping the PGE inclusions we could reveal a large variety of compositions within a single object. In addition to the expected Ir-Os-Ru system inclusions, we could also show for several inclusions the presence of another element, Pt. For a region where PGE inclusions overlap the joining area we could show that fast mapping allows to determine the compositions of the inclusion, the brazing alloy, and the base-alloy.
By using this setup, we could determine the elemental distribution of major elements Au, Ag and Cu on the different joining regions, estimate the composition of the brazes, and show that they were produced by adding Cu to the base gold alloy. By fast mapping the PGE inclusions we could reveal a large variety of compositions within a single object. In addition to the expected Ir-Os-Ru system inclusions, we could also show for several inclusions the presence of another element, Pt. For a region where PGE inclusions overlap the joining area we could show that fast mapping allows to determine the compositions of the inclusion, the brazing alloy, and the base-alloy.
Research Interests:
Recent results from a three-yearmulti-disciplinary project on Ancient Egyptian gold jewellery revealed that items of jewellery from theMiddle Kingdom to the New Kingdom weremanufactured using a variety of alluvial gold alloys. These... more
Recent results from a three-yearmulti-disciplinary project on Ancient Egyptian gold jewellery revealed that items of
jewellery from theMiddle Kingdom to the New Kingdom weremanufactured using a variety of alluvial gold alloys.
These alloys cover a wide range of colours and themajority contain PlatinumGroup Elements inclusions. However,
in all the gold foils analysed, these inclusions were found to be absent. In this work a selection of gilded wood and
leather items and gold foil fragments, all from the excavations by John Garstang at Abydos (primarily from Middle
Kingdom graves), were examined using Scanning Electron Microscopy-Energy Disperse Spectroscopy (SEM-EDS),
X-Ray Fluorescence (μXRF), Particle Induced X-Ray Emission (μPIXE) and Double Dispersive X-Ray Fluorescence
(D2XRF). The work allowed us to characterise the composition of the base-alloys and also to reveal the presence
of Pt at trace levels, confirming the use of alluvial gold deposits. Corrosion products were also investigated in the
foils where surface tarnish was visually observed. Results showed that the differences in the colour of corrosion observed
for the foils are related not only to the thickness of the corrosion layer but also to amulti-layer structure containing
the various corrosion products.
jewellery from theMiddle Kingdom to the New Kingdom weremanufactured using a variety of alluvial gold alloys.
These alloys cover a wide range of colours and themajority contain PlatinumGroup Elements inclusions. However,
in all the gold foils analysed, these inclusions were found to be absent. In this work a selection of gilded wood and
leather items and gold foil fragments, all from the excavations by John Garstang at Abydos (primarily from Middle
Kingdom graves), were examined using Scanning Electron Microscopy-Energy Disperse Spectroscopy (SEM-EDS),
X-Ray Fluorescence (μXRF), Particle Induced X-Ray Emission (μPIXE) and Double Dispersive X-Ray Fluorescence
(D2XRF). The work allowed us to characterise the composition of the base-alloys and also to reveal the presence
of Pt at trace levels, confirming the use of alluvial gold deposits. Corrosion products were also investigated in the
foils where surface tarnish was visually observed. Results showed that the differences in the colour of corrosion observed
for the foils are related not only to the thickness of the corrosion layer but also to amulti-layer structure containing
the various corrosion products.
Research Interests:
Faux, copie, pastiche, reproduction, imitation, ce sont des mots, parmi d’autres, qui classent les objets entrés au fil des siècles dans les collections et qui ne s’avèrent pas véritablement anciens. Parmi les civilisations dont l’art est... more
Faux, copie, pastiche, reproduction, imitation, ce sont des mots, parmi d’autres, qui classent les objets entrés au fil des siècles dans les collections et qui ne s’avèrent pas véritablement anciens. Parmi les civilisations dont l’art est le plus copié et imité, nous trouvons les Etrusques. Certains faux et pastiches étrusques sont devenus fameux comme par exemple la ciste Pasinati, le chariot de Prodo, le collier aux scarabées et le sarcophage des époux au British Museum, la Diane au musée d’art de St. Louis, les bracelets articulés au musée du Louvre, les guerriers d’Orvieto au Metropolitan Museum of Art, ou encore la fibule de Préneste au musée Luigi Pigorini, dont l’authenticité est toujours discutée.
Faux modernes ou faux anciens, ces objets accumulés au long des siècles dans les collections sont réalisés à partir des moyens techniques, des savoir-faire des artisans et selon le goût de l’époque. Pour les identifier et séparer des vraies productions il suffit d’avoir l’habilité de percer leurs secrets grâce aux techniques physico-chimiques qui apportent des informations sur leur morphologie et les matériaux qui les constituent.
Faux modernes ou faux anciens, ces objets accumulés au long des siècles dans les collections sont réalisés à partir des moyens techniques, des savoir-faire des artisans et selon le goût de l’époque. Pour les identifier et séparer des vraies productions il suffit d’avoir l’habilité de percer leurs secrets grâce aux techniques physico-chimiques qui apportent des informations sur leur morphologie et les matériaux qui les constituent.
Research Interests:
Lors de la fouille archéologique, coordonnée par V. Adrimi-Sismani, de la tombe à tholos de l’époque mycénienne trouvée sur le site de Kasanaki (Volos, Grèce)1, ont été découverts des objets en or, notamment des perles de collier et des... more
Lors de la fouille archéologique, coordonnée par V. Adrimi-Sismani, de la tombe à tholos
de l’époque mycénienne trouvée sur le site de Kasanaki (Volos, Grèce)1, ont été découverts des objets en or, notamment des perles de collier et des feuilles. Cette tombe date de la période HR IIIA2 (2e moitié du 14e siècle av. J-C) et s’insère dans un ensemble de sites mycéniens et de tombes à tholos qui constituaient le centre légendaire d’Iolkos, cité mythique de Jason et de la fameuse expédition des Argonautes, consacrée à la recherche de la Toison d’Or jusqu’en Colchide.
Un ensemble d’objets en or provenant de la tombe à tholos de Kasanaki, constitué de
quinze feuilles, de deux disques et d’une perle de collier, a été analysé, d’une façon totalement non-invasive au moyen de techniques de faisceaux d’ions, pour chercher l’origine de l’or.
de l’époque mycénienne trouvée sur le site de Kasanaki (Volos, Grèce)1, ont été découverts des objets en or, notamment des perles de collier et des feuilles. Cette tombe date de la période HR IIIA2 (2e moitié du 14e siècle av. J-C) et s’insère dans un ensemble de sites mycéniens et de tombes à tholos qui constituaient le centre légendaire d’Iolkos, cité mythique de Jason et de la fameuse expédition des Argonautes, consacrée à la recherche de la Toison d’Or jusqu’en Colchide.
Un ensemble d’objets en or provenant de la tombe à tholos de Kasanaki, constitué de
quinze feuilles, de deux disques et d’une perle de collier, a été analysé, d’une façon totalement non-invasive au moyen de techniques de faisceaux d’ions, pour chercher l’origine de l’or.
Research Interests:
Analytical examination of the heart-scarab (EA7876) belonging to a King Sobekemsaf has produced new evidence on its production. The heart-scarab, with its unusual inscription containing incomplete hieroglyphs, was acquired from Henry... more
Analytical examination of the heart-scarab (EA7876) belonging to a King Sobekemsaf has produced new evidence on its production. The heart-scarab, with its unusual inscription containing incomplete hieroglyphs, was acquired from Henry Salt’s collection and entered the British Museum in 1835. It was allegedly found inside
the coffin of King Nubkheperre Intef and has been linked to King Sekhemre Shedtawy Sobekemsaf whose tomb at Thebes was sacked, as evidenced by the robbers’ confessions recorded in the Abbott and Amherst papyri (c.1110 bc).
The heart-scarab was examined and analysed by optical microscopy, X-radiography, X-ray fluorescence spectrometry, scanning electron microscopy with energy dispersive X-ray spectrometry, Raman spectroscopy, Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry to determine the materials
and techniques used in its production. The results are compared with those for other objects in the British Museum belonging to King Nubkheperre Intef in order to understand any possible chronological and material link with the scarab; these are a finger-ring (EA57698), bearing the prenomen of King Nubkheperre and spacer-bars from a bracelet (EA57699 and EA57700), belonging to his wife, Queen Sobekemsaf, both dated with more certainty to the Seventeenth Dynasty.
the coffin of King Nubkheperre Intef and has been linked to King Sekhemre Shedtawy Sobekemsaf whose tomb at Thebes was sacked, as evidenced by the robbers’ confessions recorded in the Abbott and Amherst papyri (c.1110 bc).
The heart-scarab was examined and analysed by optical microscopy, X-radiography, X-ray fluorescence spectrometry, scanning electron microscopy with energy dispersive X-ray spectrometry, Raman spectroscopy, Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry to determine the materials
and techniques used in its production. The results are compared with those for other objects in the British Museum belonging to King Nubkheperre Intef in order to understand any possible chronological and material link with the scarab; these are a finger-ring (EA57698), bearing the prenomen of King Nubkheperre and spacer-bars from a bracelet (EA57699 and EA57700), belonging to his wife, Queen Sobekemsaf, both dated with more certainty to the Seventeenth Dynasty.
Research Interests:
3D representations were made of a small Egyptian scarab with a gold band by a number of methods, based on photogrammetry and photometric stereo. They were evaluated for colour fidelity and spatial detail, in the context of a study of... more
3D representations were made of a small Egyptian scarab with a gold band by a number of methods, based on photogrammetry and photometric stereo. They were evaluated for colour fidelity and spatial detail, in the context of a study of toolmarks and manufacturing techniques of jewellery in ancient Egypt. It was found that although a 3D laser scanner gave the best geometric accuracy, the camera-based methods of photogrammetry and photometric stereo gave better representation of fine detail and colour on the object surface.
Research Interests:
Présentation de la méthode d'analyse de monnaies de bronze par activation avec des neutrons rapides et analyse des résultats obtenus pour les bronzes d'Amphipolis (IVe s.) et pour des séries de bronzes de Thasos et de Maronée. Les bronzes... more
Présentation de la méthode d'analyse de monnaies de bronze par activation avec des neutrons rapides et analyse des résultats obtenus pour les bronzes d'Amphipolis (IVe s.) et pour des séries de bronzes de Thasos et de Maronée. Les bronzes ordinaires du IVe s. possèdent une teneur maximum en étain (autour de 15 %), et pratiquement pas de plomb. Le plomb apparaît d'abord
dans des émissions exceptionnelles du IVe s., dont la valeur semble avoir été fortement surévaluée. Par la suite, il semble bien que la teneur en plomb augmente, au détriment de l'étain, dans le courant de l'époque hellénistique. Ce facteur permet de sérier les séries de bronze d'Amphipolis dont le classement restait très confus.
dans des émissions exceptionnelles du IVe s., dont la valeur semble avoir été fortement surévaluée. Par la suite, il semble bien que la teneur en plomb augmente, au détriment de l'étain, dans le courant de l'époque hellénistique. Ce facteur permet de sérier les séries de bronze d'Amphipolis dont le classement restait très confus.
Research Interests:
Le présent manuel a été conçu comme une initiation à la physico-chimie des archéomatériaux, ces derniers pouvant être considérés comme les matériaux constitutifs des artéfacts et des écofacts de notre patrimoine culturel. Nous montrerons... more
Le présent manuel a été conçu comme une initiation à la physico-chimie des archéomatériaux, ces derniers pouvant être considérés comme les matériaux constitutifs des artéfacts et des écofacts de notre patrimoine culturel. Nous montrerons en particulier comment les stigmates enregistrés par les matériaux archéologiques et culturels à l’échelle microscopique, voire nanoscopique, et au niveau de leur composition élémentaire, isotopique, moléculaire et structurale, permettent de contribuer à la construction de chronologies des temps anciens, d’appréhender les comportements alimentaires, techniques et symboliques des populations du passé, de contribuer à une meilleure connaissance de la genèse des oeuvres, de déterminer l’organisation socio-économique et les réseaux d’acquisition et d’échanges des sociétés, d’aborder la question des processus de migration, d’étudier les relations Hommes-milieux, ou encore de mieux comprendre les processus d’altération afin de concourir à une meilleure conservation des oeuvres et à leur éventuelle restauration.