Pottery Samples Research Articles

The use of INAA technique in provenance studies of ancient pottery from the Greater Accra region of Ghana

The field of Archaeological in Ghana has been in existence for a very long time, gaining respect in some areas in the West African sub-region. The history of some early societies in Ghana with relation to pottery making and its uses still has a lot to be discovered. Provenance or source analyses are vital in exchange studies by finding the sources of artifacts. Through characterization studies, archaeological materials can be shown to have originated from particular areas enabling archaeologists to demonstrate human interaction. The Ga (Ayawaso) and the Dangme-Shai had cultural contacts and trade with neighboring towns and with the various European factors that traded in the coasts of Accra. The archaeological material remains recovered from these communities (Ayawaso, Wullf and Shai) during excavation were investigated using Scientific Nuclear Analytical technique. In all, the concentrations of 15 trace elements (i.e. Ce, Co, Cr, Eu, Fe, Hf, La, Lu, Mn, Rb, Sc, Ta, Tb, V, Yb) were determined in 40 pottery samples and clay samples from Afuamang (Ayawaso) and Doryumu (Shai) using instrumental neutron activation analysis (INAA). Raw clay samples from Doryumu and Afuamang normalized perfectly with pottery samples from the Shai and Ayawaso Township, respectively. Pottery samples from Wullf also normalized well with clay from Afuamang than it did with those from Doryumu. This is construed that the Wullf community did not produced their own pots but traded more with the potters from Ayawaso which was the closest potting town.

Large sample NAA work at BARC: Methodology and applications

Large sample neutron activation analysis (LSNAA) was carried out using thermal column facility of Apsara reactor at Bhabha Atomic Research Centre, Mumbai, India. The k 0-based internal monostandard NAA (IM-NAA) using in situ detection efficiency was used to analyze large and non-standard geometry samples of clay pottery, uranium ore and stainless steel. Elemental concentration ratios with respect to Na as a monostandard were used in the study of pottery and ore samples. For stainless steel sample of SS 304L, the absolute concentrations were calculated from concentration ratios by mass balance approach since all the major elements (Fe, Cr, Ni and Mn) were amenable to NAA. Applications of LSNAA in the above-mentioned three different areas are described in this paper.

Production technology and provenance study of archaeological ceramics from relevant sites in the Alcantara River Valley (North-eastern Sicily, Italy)

In this paper, volcanic-rich ceramic remains from the archaeological sites of Francavilla, Naxos and Taormina (Province of Messina, North-eastern Sicily) were studied by using inclusions as main provenance marker. Technological features, such as temper choice, vitrification degree and firing temperatures, were investigated by polarizing microscopy, X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Information on the production centres was obtained through the identification of the source area of raw materials used as temper. Indeed, petrochemical analysis of the volcanic inclusions within the examined ceramics displayed strong affinities with structures/textures and compositions of the locally outcropping mugearitic products, probably ascribed to the eruptive activity of an eccentric vent of Mt. Etna (Mt. Mojo). A local production for the studied pottery samples has been therefore advanced, assuming that the used volcanic temper was easily available from the alluvial deposits along the Alcantara River stream, which is connected to the lava flow of Mt. Mojo.

Microscopy, porosimetry and chemical analysis to estimate the firing temperature of some archaeological pottery shreds from India

In recent times, science and technology have been applied to the world of cultural heritage, preservation and conservation. In the present study, the pottery samples belonging to 4th century were collected from Tandikkudi in Dindugul district of Tamilnadu, India and were subjected to chemical analysis to outline the information about the raw materials and technological–productive aspect such as firing temperature. Investigations such as Scanning Electron Microscope and Energy Dispersive Spectrometer (SEM/EDS) are also done for the accurate observation of the morphology and the qualitative and Semi-quantitative determination of the chemical elements present in the sample. The firing temperature of the samples at the time of manufacturing is also estimated from apparent porosity of the samples which agrees well with the SEM analysis. The results obtained from different analytical techniques on pottery shreds provide information of the firing temperature of the pottery which lies in the range of 800 °C–1000 °C in the oxidizing atmosphere. Moreover it was observed that the samples collected from this site are low refractory in nature and the artisans of Tandikkudi have used both calcareous and non-calcareous clays for their household utilities, but were unaware of firing their artifacts at reduced atmosphere or closed kiln. Hence this paper is a useful analytical tool for predicting the firing atmosphere, type of clay (calcareous, non calcareous) and its nature (fine and coarse). Hence this paper is suitable for estimating the firing temperature of ancient potteries.

CHEMICAL–MINERALOGICAL ANALYSES AND MICROSTRUCTURAL STUDIES OF PREHISTORIC POTTERY FROM RAHMATABAD, SOUTH‐WEST IRAN*

A series of prehistoric pottery samples excavated from Rahmatabad, south‐west Iran, were investigated using XRF and XRD analyses to determine their chemical and mineralogical compositions. The sample microstructures were also studied by SEM/EDX. The relative similarity of compositions, the fine, dense and homogeneous microstructures and the presence of high‐temperature phases such as diopside and mullite showed the use of high firing temperatures, in the range 950–1050°C. This, along with the homogeneity in shape, decoration and size ranges of the ware, all indicate the adoption of specialized pottery‐making techniques by the potters of Rahmatabad in the fifth to fourth millennia bc.

High-Technology Manufacturing of 5th Millennium B.C. Pottery in Italy

The study of some samples of Italian Neolithic pottery (5th millennium B.C.) have put into evidence that high-level standardized techniques were adopted in the production of a peculiar ware decorated with red and black bands. High firing temperatures were a standard, aiming to obtain surface sintered layers and possibly a sort of “glaze.” The red pigments were basically “ochre” (Fe3+-oxides and clay). The nature of the black pigment is still uncertain, but it suggests that Fe2+ and not Mn-oxides were used.

Technological features of ‘gnathia’ pottery

Abstract‘Gnathia’ pottery samples, dating back to the mid‐fourth and third century BC, from the archaeological site of Egnazia (Fasano, Brindisi, Italy) have been characterised from the physical‐chemical, mineralogical and morphological points of view. Optical and scanning electron microscopy, X‐ray energy‐dispersive spectroscopy and X‐ray diffraction analyses have been carried out on the ceramic body, black gloss, white, yellow and red over‐paintings of fragments, with the aim of outlining technological features and defining the nature of coatings and decorations. Analytical results confirm from both a technological and morphological/decorative point of view the close relationship between ‘Gnathia’ pottery and red figured pottery, particularly with the Apulian red figured from which it takes its inspiration. At the same time the experimental results highlight shared characteristics and differences with both Attic and Apulian red figured productions. The biggest difference is in the utilisation of the ‘ingobbio rosso’ layer that covers the ceramic body. This does not seem to be based on aesthetic grounds, as in the case of Apulian red figured pottery, but on application of acquired production processes, since ‘Gnathia’ pottery was made in the same workshops as red figured pottery. Copyright © 2009 John Wiley & Sons, Ltd.

Characterization of pottery from Cerro de Las Ventanas, Zacatecas, México

With the aim of classifying prehispanic pottery from Cerro de Las Ventanas site, Juchipila, Zacatecas, Mexico, instrumental neutron activation analysis (INAA) was used to analyze ceramic samples at the University of Missouri Research Reactor Center. Thirty-two chemical elements were measured: Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Ti, Th, U, V, Yb, Zn, and Zr. Two multivariate statistical methods, cluster analysis and principal component analysis, were performed on the dataset to examine similarities between samples and to establish compositional groups. The statistical analyses of the dataset suggest that the pottery samples form a unique chemically homogeneous group, with the exception of one pottery sample. The compositional data were compared to an existing Mesoamerican ceramic database. It was found that the newly generated data fit best with data from a previous chemical analysis of pottery from the Malpaso Valley. However, despite the apparent similarity, pottery samples from the site of Cerro de Las Ventanas represent a new and unique chemical fingerprint in the region.

Magnetic properties and archeointensity determination on Pre-Columbian pottery from Chiapas, Mesoamerica

Abstract As part of the effort to establish an archeointensity variation curve for Mesoamerica, 13 archeologically well-identified pottery samples belonging to the Ocozocoautla site (Chiapas) were studied. Analyzed samples consist of ‘ofrenda type’ pottery fragments found in several caves. Three archeological intervals are involved: 450-100 B.C., 200–550 A.D. and 550–900 A.D. The Thellier method in its modified form was applied to small fragments previously embedded in salt pellets. Raw intensity values were further corrected for cooling rate effects. The common time-consuming TRM anisotropy correction protocol was substituted by an alternative approach during the paleointensity experiments. Forty-two specimens, belonging to six samples, yielded high-quality Thellier determinations. The NRM fraction f used for paleointensity determination ranges between 0.42 to 0.99, and the quality factor q (Coe et al., 1978) varies from 4 to 59, being normally greater than 5. These results correspond to data of good quality. The mean archeointensity values per pottery fragments range from 14.6±1.5 to 59.5±13.8 μT, while the corresponding virtual axial dipole moments range from 2.5±0.3 to 10.0±2.4 × 1022 A m2. These new data, although not numerous, are of high quality and definitively contribute to the Mesoamerican, still insipient, archeointensity database.

Archaeometric analyses of Early and Middle Neolithic pottery from the Pian del Ciliegio rock shelter (Finale Ligure, NW Italy)

The Neolithic site of Pian del Ciliegio is a rock shelter located in the Ponci Valley, at 220 m asl, in the Finalese (Liguria, NW Italy), a well-known karstic area characterised by the existence of several caves with prehistoric occupation. Archaeometric investigations (by optical microscopy and XRPD) were carried out on pottery samples mostly belonging to the Square-Mouthed Pottery Culture and the Impressed Ware Culture found out in the recent excavations of this site. Several fabrics were distinguished among the Square-Mouthed Pottery Culture pottery, suggesting different raw materials sources and production techniques. However, the nature of the mineral inclusions indicates in all cases local or circum-local production (e.g. within a range of a maximum of a few ten kilometres). All Square-Mouthed Pottery fabrics, in fact, contain elements that can be referred to the Palaeozoic metamorphic rocks outcropping in the area. In most cases they are associated with angular sparry calcite inclusions, possibly added as temper, which is a typical feature of other Neolithic pottery production from cave contexts studied in the area. On the contrary the Impressed Ware, although represented by a few sherds, shows a great variability both in fabrics and raw material provenance. Together with different local fabrics (with metamorphites ± calcite), fabrics with ophiolitic inclusions (possibly from Tuscany) and volcanic temper (from Central Italy) were found too. These data confirm and integrate those resulting from the investigation of the neighbouring Arene Candide cave site: a long-distance movement by sea of people and goods, pottery included, during the Early Neolithic is now clearly demonstrated.

Archaeometric data on production and circulation of Neolithic Serra d’Alto ware in southern Italy during the fifth millennium BC

Mid/Late Neolithic Serra d’Alto ware was widely diffused in southern Italy during the fifth millennium BC and shows homogeneous formal and technical features. Its wide distribution and frequent occurrence in funerary or cultual contexts have led many scholars to emphasise its exchange value. The issue of the circulation of finished pots rather than of a production model in different areas of Southern Italy, is explored by means of petrologic, mineralogical and chemical analyses of pottery samples from Apulia, Basilicata and Calabria. The mineralogical and chemical components of the Apulia and Basilicata samples fit very well with those of the Plio-Pleistocene silty clays of the Bradanic Trough, although major and trace element concentrations are significant in distinguishing different sub-groups of pottery related to their precise geographical setting. Calabrian pottery shows the exploitation of a local non-Apulian clay source. The strong similarities in technological processes and the formal analogies between pots found at distant Neolithic sites all over southern Italy does not correspond, then, to an actual exchange of finished pots produced in Apulia or Basilicata. A large network of middle-distance exchange of formal and technological models of production, between many Neolithic sites located in different geographical areas, is therefore proposed.

The use of FT-IR as a screening technique for organic residue analysis of archaeological samples

A range of archaeological samples have been examined using FT-IR spectroscopy. These include suspected coprolite samples from the Neolithic site of Çatalhöyük in Turkey, pottery samples from the Roman site of Silchester, UK and the Bronze Age site of Gatas, Spain and unidentified black residues on pottery sherds from the Roman sites of Springhead and Cambourne, UK. For coprolite samples the aim of FT-IR analysis is identification. Identification of coprolites in the field is based on their distinct orange colour; however, such visual identifications can often be misleading due to their similarity with deposits such as ochre and clay. For pottery the aim is to screen those samples that might contain high levels of organic residues which would be suitable for GC–MS analysis. The experiments have shown coprolites to have distinctive spectra, containing strong peaks from calcite, phosphate and quartz; the presence of phosphorus may be confirmed by SEM–EDX analysis. Pottery containing organic residues of plant and animal origin has also been shown to generally display strong phosphate peaks. FT-IR has distinguished between organic resin and non-organic compositions for the black residues, with differences also being seen between organic samples that have the same physical appearance. Further analysis by GC–MS has confirmed the identification of the coprolites through the presence of coprostanol and bile acids, and shows that the majority of organic pottery residues are either fatty acids or mono- or di-acylglycerols from foodstuffs, or triterpenoid resin compounds exposed to high temperatures. One suspected resin sample was shown to contain no organic residues, and it is seen that resin samples with similar physical appearances have different chemical compositions. FT-IR is proposed as a quick and cheap method of screening archaeological samples before subjecting them to the more expensive and time-consuming method of GC–MS. This will eliminate inorganic samples such as clays and ochre from GC–MS analysis, and will screen those samples which are most likely to have a high concentration of preserved organic residues.

Mössbauer and mineral magnetic studies on archaeological potteries from Adhichanallur, Tamilnadu, India

Megalithic potteries collected from Adhichanallur, Tamilnadu, India (Lat. 8°44′ N; Long. 77°42′ E) have been subjected to various spectroscopic and rock magnetic studies. The type of clay, their origin, level of structural deformation due to firing, firing temperature and atmospheric condition followed during making the potteries are analyzed. The potteries were subjected to Mossbauer and X-ray diffraction studies to analyze the iron phases in them. It is found that the samples were made of local clay (red clay), fired above 600°C under open atmospheric and/or reduced atmospheric conditions and air has been allowed during cooling. The Mossbauer spectra reveal the presence of Fe3 + , Fe2 + and iron oxides of hematite and magnetite. The firing temperature and firing conditions established from Mossbauer studies are similar to the observation made from FT-IR studies. The magnetic mineral types, the mass fractions and the domain states of the constituent magnetic grains were elucidated from a range of rock magnetic measurements including variation of susceptibility with low field, frequency and temperature, hysteresis parameters and isothermal remanence acquisition data. The magnetic mineralogy of most pottery samples was dominated by magnetite/(titano) magnetite, while magnetic grain size spectrum varies from very fine (super paramagnetic) to fine (stable single domain, pseudo single domain). The reversible thermo magnetic behavior reflects no mineralogical transformations during reheating and all the samples show same Curie temperature 580°C due to magnetite. From the above information it is demonstrated that these samples are suitable for determining the reliable ancient geomagnetic field intensity values existed during that period.

Analytical study of ancient pottery from the archaeological site of Aiani, northern Greece

The present study is a multi-analytical approach on the characterization of several potsherd samples, dated from prehistoric to hellenistic times, from Aiani, ancient Upper Macedonia, northern Greece. In particular, X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and Environmental Scanning Electron Microscopy, coupled with Energy Dispersive X-ray system (ESEM-EDX) were used for the determination of the morphological, chemical and mineralogical characteristics of the potsherds. The preliminary results indicated a rather local provenance of the analyzed ancient pottery samples and a finer texture and thus better ceramic manufacture as getting to hellenistic era. The use of a silicious or calcerous raw material is probably related to the specific utilization of each ceramic vessel in ancient times. The presence of gehlenite or pyroxene minerals in the ceramic matrix indicated higher firing temperatures, while lower temperatures were deduced when finding phylosilicate minerals. The preliminary results of this study do not necessarily imply that all the pottery of this area, belonging to the same chronological type, have similar physicochemical characteristics.

THE TECHNOLOGY OF PRODUCTION OF SASANIAN GLAZED POTTERY FROM VEH ARDAŠ?R (CENTRAL IRAQ)

Scanning electron microscopy coupled with an energy dispersive X‐ray detector (SEM‐EDS) has been used to study samples of Sasanian glazed pottery. Analysis of ceramic bodies revealed a general homogeneity in composition among the studied samples and the use of calcareous clay for their manufacture. Glazes are typically alkaline in composition, with sodium and potassium oxide contents between 8 and 13%, and between 3 and 5%, respectively; calcium and magnesium oxide contents are between 7 and 10%, and between 3 and 5%, respectively. These data suggest the use of plant ash together with a silica source for glaze production. Coating thickness is highly variable among different samples, from some 400 up to 1200 µm, but it is generally uniform when a single sample is concerned. Glazes are mostly coloured blue or blue‐green; copper and iron are the colouring agents detected; abundance of bubbles, silicate crystals and relics of unmelted material are responsible for their generally opaque appearance, together with the presence of weathering products. The characteristics of the body to glaze contact zone, together with the widespread presence of bubbles, would not rule out production by a single firing process. A few samples feature a peculiar gritty coating on one side of their surface; SEM images show that they are actually partially vitrified, and EDS data denote a rather heterogeneous composition. It seems possible that they result from mixing clay together with the frit used for glaze development.

Ceramic production, consumption and exchange in the Banda area, Ghana: Insights from compositional analyses

Ceramic production, exchange and consumption in the Banda area, west central Ghana has been affected by historical developments ranging from recent competition with alternative vessels (made of metal and plastic) to political economic upheavals that altered community relationships within and outside the region. In this study, we explore spatial and temporal patterning in pottery production, exchange and consumption using a combination of analytical techniques. Instrumental neutron activation analysis (INAA) of a large sample (491 specimens) of archaeological and ethnographic pottery, clay and temper samples from sites across the Banda area has led to the identification of seven compositional groups whose differential distribution implies shifts in resource selection through the last thousand years. Laser ablation-ICP-MS analysis was used to explore the effects of distinctive tempering agents (crushed slag) on the bulk chemical signature of a subset of Banda ceramics, while petrographic analysis provides insight into the preparation of ceramic fabrics. We integrate insights from these diverse physical studies to investigate the dynamics of pottery production, exchange and consumption over the course of the last millennium in the Banda area and explore potential linkages with broader political economic transformations.

Electron microscopy study of Hispanic Terra Sigillata

Two Hispanic Terra Sigillata pottery samples from different workshops – Tricio and Andujar – have been characterized by means of electron microscopy and associated techniques and X-ray diffraction data. The combined information from transmission electron microscopy images, electron diffraction patterns and microchemical analysis has revealed the nature and distribution of the precipitates of the ceramic piece slip, which is a very important part in the characterization of these kind of ceramic wares. Both samples present homogeneously dispersed α-Fe2-xAlxO3 (corundum-type structure) particles embedded in a glassy matrix of SiO2-Al2O3. The Si : Al ratio of the matrix is different in each case, with a higher Al content in the Andujar ceramic sample. Crystallites of spinel – Mg(Al,Fe)2O4 – and Al2-xFexO3 are also detected in both cases. In addition, ilmenite phase (FeTiO3) and TiO2 (rutile-type) were observed less frequently.

Chemical process to separate iron oxides particles in pottery sample for EPR dating

Ancient potteries usually are made of the local clay material, which contains relatively high concentration of iron. The powdered samples are usually quite black, due to magnetite, and, although they can be used for thermoluminescene (TL) dating, it is easiest to obtain better TL reading when clearest natural or pre-treated sample is used. For electron paramagnetic resonance (EPR) measurements, the huge signal due to iron spin–spin interaction, promotes an intense interference overlapping any other signal in this range. Sample dating is obtained by dividing the radiation dose, determined by the concentration of paramagnetic species generated by irradiation, by the natural dose so as a consequence, EPR dating cannot be used, since iron signal do not depend on radiation dose. In some cases, the density separation method using hydrated solution of sodium polytungstate [Na 6(H 2W 12O 40)·H 2O] becomes useful. However, the sodium polytungstate is very expensive in Brazil; hence an alternative method for eliminating this interference is proposed. A chemical process to eliminate about 90% of magnetite was developed. A sample of powdered ancient pottery was treated in a mixture (3:1:1) of HCl, HNO 3 and H 2O 2 for 4 h. After that, it was washed several times in distilled water to remove all acid matrixes. The original black sample becomes somewhat clearer. The resulting material was analyzed by plasma mass spectrometry (ICP-MS), with the result that the iron content is reduced by a factor of about 9. In EPR measurements a non-treated natural ceramic sample shows a broad spin–spin interaction signal, the chemically treated sample presents a narrow signal in g = 2.00 region, possibly due to a radical of (SiO 3) 3−, mixed with signal of remaining iron [M. Ikeya, New Applications of Electron Spin Resonance, World Scientific, Singapore, 1993, p. 285]. This signal increases in intensity under γ-irradiation. However, still due to iron influence, the additive method yielded too old age-value. Since annealing at 300 °C, Toyoda and Ikeya [S. Toyoda, M. Ikeya, Geochem. J. 25 (1991) 427–445] states that E ′ 1 -signal with maximum intensity is obtained, while annealing at 400 °C E ′ 1 -signal is completely eliminated, the subtraction of the second one from 300 °C heat-treated sample isolate E ′ 1 -like signal. Since this is radiation dose-dependent, we show that now EPR dating becomes possible.

Technological features of Apulian red figured pottery

Apulian red figured pottery samples, dating back to the 5th and 4th centuries BC, from the archaeological site of Monte Sannace (Gioia del Colle, Bari, Italy) have been characterized from the physical–chemical, mineralogical and morphological points of view. Scanning electron microscopy, X-ray diffraction and atomic spectroscopy investigations have been carried out on the ceramic body, red decorated area and black gloss of the fragments, with the aim of outlining the technological features and of defining the nature of coatings and decorations. All 5th century fragments show the same features: fine texture of the ceramic body, red figures saved from the ceramic paste and black gloss painted directly on the ceramic body. The statistical treatment of compositional data of ceramic bodies excludes the local production of these objects. As regards the 4th century fragments, some show similar features to the 5th century ones; however others are characterized by the coarse texture of their ceramic body and an intermediate red layer of finer clay between the black gloss and the ceramic body. The analytical results make it possible to distinguish two different production technologies of red figured Apulian vases in Monte Sannace during the 4th century BC. Certain vases were produced using the “classic” Attic technology and others with a different technique, not previously known, which involved the application of a red engobe layer on the clay paste, before the black gloss painting.

TL and OSL Dating of Sediment and Pottery from Two Syrian Archaeological Sites

Luminescence dating is widely applied nowadays, mainly for archaeological material and artefacts and sediments of all types and origins. However, optically stimulated luminescence (OSL) from archaeological sediment, originated from mud brick buildings has been hardly studied. The archaeological sites of Tall Abu Fahd and Tall Qsubi are located in the Middle Euphrates Valley, Deir ez-Zor district, Syria. These two Bronze Age sites were recently discovered by a Spanish-Syrian team from the Directorate General of Antiquities and Museums (Damascus) and the University of Coruña. Both sites were dated (about 3.5 ka BC) by typological pottery classification. Sediment and pottery samples from these archaeological sites were collected for luminescence dating. Several analytical procedures for obtaining equivalent doses were tested on the sediment samples. Blue OSL from quartz subsamples and IRSL, post IRSL Blue OSL from feldspar contaminated quartz and polymineral subsamples were performed to obtain OSL ages. For the pottery samples, additive dose TL on a coarse grain feldspar contaminated quartz subsample was performed as well. Results have shown agreement among all the luminescence procedures tested on the Tall Abu Fahd site samples after fading correction, showing ages around 2.7 ka BP. Obtained ages from the other site samples show disagreement among quartz blue OSL and the other subsamples. Fading ratios allow correcting age underestimations from the polymineral post-IR OSL signal. However, the polymineral IRSL signal still shows underestimation. Final sediment and pottery ages have shown good agreement. Older <sup>14</sup>C independent age (3.32 ka BP) corresponds to occupational periods of the site while sediment ages are attributed to a post occupation phase.