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1.
The pervasive crystallization of secondary phosphates in pores and fractures of numerous potsherds from the archaeological site of Frattesina (Fratta Polesine, Rovigo – North-East Italy) indicates that contamination occurred after burial. The chemical composition of these phases, which are Mg-rich vivianite and mitridatite, shows that sources of phosphorus, calcium, iron and magnesium were locally available and that the precipitation and diagenesis of these minerals were strongly influenced by micro-environmental conditions within the archaeological deposit.  相似文献   

2.
The aim of this study is practically to establish a chemical strategy for cleaning soiled deposits and encrustations on archaeological glasses. Investigations were performed on a series of Roman glass samples (Fragments and complete objects) coming from different excavations in northern Jordan. The chemical composition of the glass samples was determined by X-ray fluorescence spectrometer (XRF) analysis technique, whereas X-ray powder diffractometer (XRD) and Energy dispersive X-ray (EDX) methods were used to determine the mineralogical and elemental composition of the soiled deposits and encrustations on the glass surfaces. Furthermore, Scanning Electron Microscopy (SEM) examination and optical assessment were performed before and after cleaning glass. The glass samples were subjected to different cleaning protocols such as Calgon (Sodium hexametaphosphate), ethylenediaminetetraacetic acid (EDTA) at different pH values, citric and tartaric acids and piranha solution (a solution of sulphuric acid and hydrogen peroxide). Sepiolite poultices soaked by chemical agents were the most suitable methods used for applying chemical solutions on the glass surface. It can be concluded that EDTA is generally accepted as the most effective chelating agents recommended for cleaning encrustations on durable glass. It was more effective and safe at neutral pH with low concentrations around 5 to 7%. The calcareous crusts can safely be removed by using a piranha solution. Citric and tartaric acids appeared a moderate efficiency on cleaning weathered and stable glass. Calgon has a tendency to damage corroded and iridescent surfaces, and should be avoided when cleaning weathered glass.  相似文献   

3.
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties.  相似文献   

4.
Using inductively coupled plasma–atomic emission spectrometry (ICP-AES), atomic absorption spectrometry (AAS) and instrumental neutron activation analysis (INAA) the concentration of Ag, As, Au, Bi, Cu, Fe, Ga, In, Ni, Sb, Sn, and Zn in 53 samples taken from archaeological finds dated to 4th–2nd century BC and found in the territory of ancient Thracia was determined. Additionally using inductively coupled plasma–mass spectrometry (ICP-MS) and MS for determination of the lead isotope ratios in the samples was carried out. On the basis of these analytical results using cluster analysis for grouping the samples on the bases of the similarity in chemical and isotopic content and the available data from the literature for lead ore deposits in the Balkan Peninsula, the geological origin of the investigated archaeological finds was evaluated. That confirms the expectation that sources of lead might be almost all possible deposits of lead ores on the Balkan Peninsula—from Lavrion through Chalkidiki to the Rhodope mountain. The result indicates that the Thrace did not utilize one single lead source continuously but that lead was provided according to availability from different production centers.  相似文献   

5.
This work is focused on the petro-archeometric characterization of the fine pottery production of the archaeological site of Gela (Sicily). Thirty-five samples coming from three Archaic and Hellenistic kilns and five coming from an Hellenistic house, were investigated by means of optical microscopy, XRD and XRF analysis. With the exception of some ceramics which are undoubtedly imported, all the samples have similar petrographic features, but on the basis of chemical composition, we can distinguish two different groups. The presence of two local productions is confirmed by the comparison with locally outcropping sediments and with archaic and modern bricks of sure Geloan production. This result is particularly significant for the definition of reference groups of this wealthy polis that played an important trading role in the Mediterranean area.  相似文献   

6.
An archaeological excavation has been carried out at Pisa (Italy), unearthing an ancient metallurgical workshop. Since archaeological burnt materials provide important records of direction and intensity of the Earth's magnetic field in the past and they can be used to better improve geomagnetic secular variation curves (SVCs), an archaeomagnetic study has been performed. This small copper-alloy furnace presents a circular concave shape covered with a thin layer of mortar, with some traces of heated clay surrounding the feature that confirms the high temperature reached inside it. Archaeological context dating points to the last firing of the furnace between the last quarter of the 13th century and the first quarter of 14th century AD, when then the metallurgical workshop was transformed in a warehouse. Archaeomagnetic sampling has been performed using the modified Thellier method, by collecting several, large and independently oriented aliquots of heated clay, forming the bottom part of the circular wall of the structure. Laboratory treatments have been conducted at the IGG-CNR ARCHEO_LAB (Pisa, Italy) and at St. Maur Palaeomagnetic laboratory (Paris, France). Analytical measurements of the thermo-remanent magnetization index acquired from the samples have been performed using a large cell induction magnetometer for large samples, and the characteristic remanent magnetization (ChRM) has been successfully isolated after an alternate field demagnetization cleaning procedure for each sample. The final mean archaeomagnetic direction has been calculated at sampling site (D = 6.9°; I = 52.8°; N = 9; k = 305; α95 = 2.6°) following the Fisher Statistics, and it exhibits a perfect agreement with some coeval already published directions obtained from Mt. Arso lava flows, these latter being an important anchor point in the preliminary Italian secular variation curve. Comparison with the preliminary Italian SVC, the French SVC and the SCHA.DIF.3K archaeomagnetic regional model have permitted to define an archaeomagnetic absolute age confirming the conventional archaeological age, underlining the importance of this result into the Italian archaeomagnetic data set.  相似文献   

7.
This paper deals with the comparative evaluation of different procedures of salt extraction designed for archaeological ceramics from submarine burial environments. The experimental work was carried out on a particular type of late-Roman cooking ware finds (Pantellerian ware) found in a shipwreck near the shoreline of the Island of Pantelleria (Sicily). The studied ceramic test-pieces were first recognised in terms of bulk characteristics (mineralogy, petrography and chemistry). SEM-EDS observation allowed verification of the presence of various secondary minerals at the surface and in the pore spaces formed after the prolonged permanence in seawater under oxidising or reducing conditions. Pore-size distribution was also determined in the same fragments that had been subjected to the salt extraction routines. Three salt extraction methods were tested: two methods based on diffusion processes (water immersion under stationary conditions and under mechanical stirring conditions) and one method based on both diffusive and advective processes (multiple packages of sepiolite). The obtained experimental data allowed us to identify strengths and weaknesses of the tested procedures with practical spin-off for archaeologists and restorers (efficiency, kinetics, compatibility with the ceramic substrate, costs and simplicity of use). Salt extraction under mechanical stirring was the most effective method and, for this reason, is suitable for laboratory fieldwork during or immediately after submarine archaeological excavations. Similar advantages are also intended for the preliminary treatments of the most precious findings prior to museum storage.  相似文献   

8.
Analysis of historic mortars including Islamic, Gothic and later ones taken from palaces, convents and mansions in Palma de Mallorca has been carried out. Scanning electron microscopy (SEM) coupled to energy dispersive X-ray spectrometer (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) techniques were used to characterise the morphology and analytical composition of the samples analysed. Generally, covering plaster mortars presented a low percentage of small size aggregate. The reported results show that mixed and lime mortars have been used, thus, the establishment of a relationship between the type of mortar employed and its age is not feasible. In the painted mortars, polychromy has also been studied. The most common pigments to be found are natural earths.  相似文献   

9.
The aim of this work is to show how the most advanced technology together with spatial analysis can be usefully employed to investigate historical and archaeological phenomena. In this note some preliminary results are shown. Two geographical information systems (GIS) were structured in an integrated way. The first GIS is a vector-like system while the other is a raster-like one. Moreover, some applications regarding the environmental reconstruction of a part of the investigated area are proposed. Then the identification and the modeling of archaeological site maps by means of point pattern analysis are proposed. Finally, an auto-logistic model to predict archaeological site is presented. This topic is currently under investigation.  相似文献   

10.
Hyperspectral data were exploited to test their effectiveness as a tool for archaeological prospection, envisaging their potential for detecting spectral anomalies related to buried archaeological structures. For this purpose the airborne Multispectral Infrared and Visible Imaging Spectrometer images were analysed. Each single band of the entire data set and different processing technique products were interpreted to identify any tonal anomalies. Since every analysed image exhibited marks different in terms of size and intensity, two indexes were defined for assessing the potential of anomalies detection of each image. Such parameters were: the Detection Index, used for counting the number of pixels related in each image to marks, and the Separability Index, applied for measuring the tonal difference of the marks with respect to the background. These indexes were tested on two areas within the Selinunte Archaeological Park where the presence of remains, not yet excavated, was supposed by archaeologists. For the test sites any extracted anomalies were evaluated by an expert in order to determine their archaeological relevance. The comparison among the index values, derived from each single band of the spectrometer and from different image processing by-products, allowed to determine which spectral range and which processing method are the most valuable to quickly highlight the anomalies. The analysis pointed out that, where vegetation cover is dominant, the Visible near infrared is the spectral region more sensitive to variations of spectral properties related to buried structures, while, where soil cover becomes relevant, the Short-wave infrared and the Thermal-infrared regions resulted more sensitive. As far as the applied processing methods are concerned, the Spectral Angle Mapper classifier and, secondly, the Minimum Distance algorithm stressed the highest archaeological information content. The results of this work showed that the archaeological information content derived by analysing the outputs of the applied image processing techniques is more significant than the information obtained by interpreting each single band and the available historical aerial photos. As a final remark, the data processing flow chart, applied to the entire remote hyperspectral data set over Selinunte Archaeological Park, appeared encouraging for detection of anomalies related to the presence of the buried archaeological structures.  相似文献   

11.
A group of 51 shards of medieval polychrome glazed pottery, coming from Canosa castle archaeological site (Bari, Italy), has been investigated through surface analytical techniques, such as Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS) and elemental ones, such as Inductively Coupled Plasma–Optical Emission Spectroscopy (ICP–OES) and Absorption Atomic Spectroscopy (AAS) by flame and electro-thermal atomisation. The investigation was aimed at defining the elemental composition of pottery findings, identifying pigments and clarifying glaze types. The results of the analytical characterization allowed the identification of materials and technological expedients used for pottery manufacturing, highlighting original features in the production of the investigated pottery.The quantitative analysis performed on ceramic paste, glaze and painted decorations provided a significant number of results, thus enabling their effective exploitation for multivariate statistical techniques, in order to find out possible groups of pottery items with defined similarity within the samples.  相似文献   

12.
In March 1997 the excavation team of Edward Keall, Head of the Department of Near Eastern and Asian Civilization of the Royal Ontario Museum, Toronto (Canada) found the remains of an apparently prehistoric site in a region that was supposed to have been uninhabited until the Middle Ages. On the site there are megalithic pillars of granite and basalt, weighing around 6 tons; some were part of what looks like a rectangular building. A cache of copper-based objects – consisting of two adzes, two daggers, four points, two razors and a leaf-shaped object – was found under one of the fallen megaliths. The authors present the as yet unpublished results of the chemical analysis carried out by ICP and the observations obtained by SEM/EDX and discuss briefly the significance of the data and the problems encountered while studying the items of the newly discovered civilization. The stylistic comparisons and the chemical composition of the objects suggest a date around the end of the 3rd or the beginning of the 2nd millennium BC, while other finds on the site seem to indicate a later period.  相似文献   

13.
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14.
The analysis of the amino acid (AA) content in fragments derived from a prehistoric rock pictograph (Lancusi rock shelter) at Tadrart Acacus, southern west Libya, revealed the presence of material containing peptides differing in solubility in hot acidic or alkaline solutions, as well as in AA composition and racemization. Water-soluble components were constituted of low molecular weight peptides with high racemization of aspartic acid and alanine, whereas the water insoluble material consisted of species of a more complex AA composition and a different degree of racemization. The proteinaceous materials were assumed to originate from matter that had undergone over time different diagenetic processes. The water insoluble peptide-containing material was separated from the rock substrate by acid hydrolysis, dried and the resulting residue submitted to radiocarbon analysis. Accelerator mass spectrometry (AMS) yielded an approximate age of 6145 ± 70 years B.P. (before present), which is consistent with archaeological inference and the climatic reconstruction of central Sahara. To our knowledge the present work represents the first attempt of direct radiocarbon dating of rock art in the Sahara desert.  相似文献   

15.
The “marble” Portasanta from Caldana (Grosseto, Italy) takes its name from the strict resemblance to the ancient Marmor Chium (also this called Portasanta) coming from the island of Chios in Greece. In this work, a complete characterization of the Italian Portasanta was made: chemical (X-ray fluorescence and isotopic analyses), mineralogical (X-ray diffraction on the bulk sample and on insoluble residue after acid attack), physical (water accessible porosity and imbibition coefficients), petrographical (optical microscopy) and mechanical (compressive strength test) analyses have been carried out in order to obtain a better distinction between Italian and Greek “marble”, sometimes mistaken. The Portasanta from Caldana (Italy) was quarried surely in the sixteenth century, but a possible use of this material during Roman time is still in doubt. The study of samples from some Tuscan archaeological sites (Torraccia di Chiusi, Siena and Roselle, Grosseto) allows us to confirm the use of Portasanta from Chios for the Torraccia site and that of Caldana for Roselle.  相似文献   

16.
Safeguarding and exploiting Cultural Heritage induce the production of numerous and heterogeneous data. The management of these data is an essential task for the use and the diffusion of the information gathered on the field. Previously, the data handling was a hand-made task done thanks to efficient and experienced methods. Until the growth of computer science, other methods have been carried out for the digital preservation and treatment of Cultural Heritage information. The development of computerized data management systems to store and make use of archaeological datasets is then a significant task nowadays. Especially for sites that have been excavated and worked without computerized means, it is now necessary to put all the data produced onto computer. This allows preservation of the information digitally (in addition with the paper documents) and offers new exploitation possibilities, like the immediate connection of different kinds of data for analyses, or the digital documentation of the site for its improvement. Geographical Information Systems have proved their potentialities in this scope, but they are not always adapted to the management of features at the scale of a particular archaeological site. Therefore this paper aims to present the development of a Virtual Research Environment dedicated to the exploitation of intra-site Cultural Heritage data. The Information System produced is based on open-source software modules dedicated to the Internet, so users can avoid being software driven and can register and consult data from different computers. The system gives the opportunity to do exploratory analyses of the data, especially at spatial and temporal levels. The system is compliant to every kind of Cultural Heritage site and allows management of diverse types of data. Some experimentation has been done on sites managed by the Service of the National Sites and Monuments of Luxembourg.  相似文献   

17.
Metallographic features of ancient bronze artefacts often hide peculiar micro-chemical processes and corrosion behaviours, which are worth to be studied as they can provide conservators and archaeologists with valuable tools and information. It is widely documented that Chinese bronzes were cast and the way to adjust their properties was to change the alloy composition. In particular, addition of lead, which is insoluble in the bronze matrix, results in the formation of inclusions or globules, which undergo oxidation processes leading to their conversion into corrosion products. The mechanisms through which this occurs were still poorly investigated. The present work was conducted to further study the corrosion behaviour of high-leaded bronze, especially focusing on the behaviour of lead globules. To this aim, a collection of Chinese archaeological bronzes, showing intermediate steps of degradation, were selected and investigated. The use of combined microscopy-based, molecular and elemental, analytical techniques allowed the characterization as well as the precise location of corrosion products, thus enabling us to propose a degradation pathway basing on thermodynamic data provided by Pourbaix diagram. The achieved results will be useful for researchers involved in these kinds of studies to better interpret data obtained.  相似文献   

18.
Late Apulian red figured pottery [1] from Egnatia (Fasano, Brindisi, Italy) was studied in order to widen the view on this ceramic class in Southern Italy. Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) provided the samples elemental composition that allowed to make provenance hypotheses. Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrometry (EDS), supplied information about the minero-petrographic features of the objects to better understand their production technology. The set of results highlighted the contemporary presence in the Apulian land in the late 4th century BC of both local and imported finds and showed the existence of two different kinds of local production, the “classic” Attic and a peculiar one, characterized by the application of an engobe layer before the black gloss. Our previous studies resulted in the discovery that an engobe layer, with similar chemical and minero-petrographic characteristics, was present in finds from another site in central Apulia (Monte Sannace). So the discovery of red engobe on fragments from Egnatia, proves that its use was not an isolated occurrence, but was quite common in the production of red figured in Apulia during the Late period, appearing as a peculiar technological mark of Apulian potters.  相似文献   

19.
Twenty lead finds, unearthed in Late Bronze–Early Iron Age levels at the Santa Barbara nuraghe situated at Bauladu in Sardinia (Italy), have been examined. Their chemical composition has been determined using the ICP-MS plasma-mass technique (Cu, Fe, As, Ag, Sn, Sb, Bi, Zn, Cs, Tl, Mo, Cd, In, Te, W, Th, U, Li, Se). Lead isotope ratios (208/206, 207/206, 206/204) have also been determined. The results are discussed in relation to the mineral source and some aspects of the metal extraction processes. The finds are composed of high purity lead obtained using a smelting at low temperature. Based on the isotope ratios it has been possible to establish that the metal originated from Sardinian ore deposits type.  相似文献   

20.
Understanding the chemical and physical alteration in archaeological bones, occurred after burial, is very interesting for researchers. In this paper, we present a study on the diagenetic alteration of human archaeological bony tissues from Paestum (South Italy), by combining complementary spectroscopic techniques, such as solid-state nuclear magnetic resonance (NMR), infrared spectroscopy (IR), and X-ray diffraction. In particular, 13C nuclear magnetic resonance–cross polarization-magic angle spinning (13C NMR CP-MAS) spectroscopy allows to identify and discriminate the adsorbed calcite, that is a diagenetic contaminant, from the structural one of apatite and 1H NMR-MAS spectroscopy shows how the degradation of organic phase of collagen is related to the time. The NMR data are combined with crystalline index, measured by X-ray diffraction, and with the splitting factor obtained by infrared spectroscopy. Moreover, the evaluation of the relative content of biogenic structural carbonate and of diagenetic fluorine is reported.  相似文献   

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