PHOSPHATES IN ARCHAEOLOGICAL FINDS: IMPLICATIONS FOR ENVIRONMENTAL CONDITIONS OF BURIAL*

The occurrence of coarse‐grained vivianite and mitridatite aggregates in a potsherd, a grand ring and a timber imprint from the Second Iron Age site of Adria (Rovigo, northeastern Italy) suggest contrasting environmental conditions of burial. In particular, bone fragments were replaced by vivianite at relatively low pH and Eh, due to the presence of deteriorating organic matter, together with slag and iron flakes. Subsequent interactions with Ca‐rich groundwater characterized by higher pH and Eh determined the growth of mitridatite after vivianite. Although phosphates crystallized after burial, the examined samples were not involved in pervasive chemical contamination.     

The geochemical diversity of neogene clay deposits in Crete and its implications for provenance studies of Minoan pottery*

The determination of provenance probably forms the primary role of geochemical analyses in archaeological ceramic studies. In what has comprised a successful field of study, the ultimate basis for such research has been the comparison of pottery compositions with the geochemical diversity displayed by clay deposits within a given study area. Although such studies are now common, the understanding of chemical and mineralogical variability in ceramic raw materials has been somewhat neglected, with the dominance of assumptions rather than the actual analysis of clays. In this paper, a study is presented of Neogene clays in Crete (Greece), a clay type commonly used in ancient and modern pottery production. Sixty‐one samples were taken from 28 locations in the central and eastern parts of the island, to reveal both intra‐ and inter‐deposit variability. In one deposit chosen for multiple sampling, the 14 samples display great variability in the alkali elements, Fe and Co, and to a lesser extent in the REEs. Many of the geographically separate deposits differ from each other in chemical composition, with Eastern Cretan deposits showing higher REE concentrations and higher Th/Sc ratios, whereas Central Cretan deposits of younger geological stages are characterized by a lower Th/U ratio. Mineralogical analysis by XRD is used to explain aspects of the geochemical variability of the clays.     

A SPECTROSCOPIC INVESTIGATION OF PIGMENT AND CERAMIC SAMPLES FROM COPÁN,HONDURAS*

A combination of micro‐Raman spectroscopy, micro‐infrared spectroscopy and SEM–EDX was employed to characterize decorative pigments on Classic Maya ceramics from Copán, Honduras. Variation in red paint mixtures was correlated with changing ceramic types and improvements in process and firing techniques. We have confirmed the use of specular hematite on Coner ceramics by the difference in intensities of Raman bands. Different compositions of brown paint were correlated with imported and local wares. The carbon‐iron composition of the ceramic type, Surlo Brown, was confirmed. By combining micro‐Raman analysis with micro‐ATR infrared and SEM–EDX, we have achieved a more comprehensive characterization of the paint mixtures. These spectroscopic techniques can be used non‐destructively on raw samples as a rapid confirmation of ceramic type.     

A COMPARATIVE ELECTRON MICROPROBE STUDY OF LERNA III AND IV CERAMICS AND LOCAL CLAY-RICH SEDIMENTS*

This study uses electron microprobe analysis of ceramic artefacts and local day-rich sediments and lithics to help address questions concerning the nature of the cultural change implied by ceramics from Lerna III and IV. It redresses the previous lack of a comparative collection of clay-rich sediments that adequately represents the local variation in clay and temper for the area surrounding Lerna. The resulting comparisons indicate that although they produced stylistically different ceramics, potters from both Lenta phases acquired their clays from the local Lerna area.     

NEUTRON ACTIVATION ANALYSIS OF ROMAN AFRICAN RED SLIP WARE KILNS

Roman African Red Slip ware (ARS) sherds from four ARS kiln sites in modern-day Tunisia (El Mahrine, El Ala, Oudna and Pheradi Maius) have been analysed using instrumental neutron activation analysis. Multivariate statistical methods (including cluster analysis and Manhattan City Block distances), with a dilution correction applied to the data, were used to interpret the concentration data. Reference groups for each of the four kiln sites were established. Both El Mahrine and Oudna were described by two dilution-related groups. These kiln groups were all shown to be compositionally distinct from each other and suitable for use in provenance studies.     

PROVENANCE STUDIES OF ROMAN AFRICAN RED SLIP WARE USING NEUTRON ACTIVATION ANALYSIS

African Red Slip ware (ARS) from Carthage and San Sisto Vecchio (Rome) was analysed by neutron activation analysis. The Carthage tableware was linked with Oudna and the type 1 lamps were probably from a northern ARS/lamp factory other than the sources currently investigated. Two samples were central Tunisian, probably manufactured at El Ala. The San Sisto samples divided into three groups and three outliers of undetermined provenance. Group 1 was central Tunisian, probably from El Ala, and was composed entirely of terra sigillata chiara C forms. Group 2 was of unknown origin within northern Tunisia. Group 3 was the largest subset and most of its constituent samples were associated with El Mahrine. Additionally, four samples were linked with Oudna.     

COMPOSITION AND ORIGIN OF IAPYGIAN POTTERY FROM ROCA VECCHIA,ITALY

We have studied 35 samples of fragments of ceramic containers dated between the eleventh and the eighth centuries BC, found at the archaeological site of Roca Vecchia, some 20 km from Lecce along the Adriatic (Salentine) coastline. Analysis of the elemental composition of the finds has been performed by means of atomic emission spectroscopy in plasma and the results obtained have been treated with diverse multivariate statistical techniques. Except for some minor differences, the statistical analysis confirms the grouping structures indicated by typological and stylistic evaluations of the samples, in accordance with the validity of the above methods.     

A PROVENANCE STUDY OF POTTERY FROM ARCHAEOLOGICAL SITES NEAR CANOSA,PUGLIA (ITALY)*

Studies have been carried out to assess the provenance of selected pottery excavated at archaeological sites near Canosa, Puglia (Italy). Sixty-six sherds, ranging in date from the mid-seventh century BC to the beginning of the third century BC, were analysed by atomic absorption spectroscopy and 16 elements were determined. The analysis data were subjected to multivariate classification procedures. Tests showed that the majority of the examined sherds came from ancient local kilns; a probable Ionian origin was established for some other sherds, while the rest were of unknown origin.     

FIRING ANALYSIS OF SOUTH-EASTERN MISSOURI INDIAN POTTERY USING IRON MÖSSBAUER SPECTROSCOPY*

The Mössbauer spectra of prehistoric pottery and clay from the Malden Plain of south-eastern Missouri, USA, were examined. The pottery dates from AD 500 to 1400. The earlier sherds were tempered with sand and the later ones with shell. The sherds and clay contain a mixture of illite, smectite, and kaolinite. Most samples of clay and sherds contained both ferric and ferrous species. The spectral parameters for the ferric species were %DLE_Q～0. 7—1.1 mms^-1 and δ～0.0–0.3 mms^-1 for the ferrous species, ΔE_Q～2.1–2.7mms^-1 and δ～0.7–1.0mms^-1. The ferric to ferrous ratio is more accurately determined from the spectra than from consideration of the colour or the firing core of the sherds, which are not always related to the iron species ratio. Differences among sherds in the ferrous ΔE_Q can be related to original temperature of heating but with low precision.     

LEAD GLAZES IN ANTIQUITY—METHODS OF PRODUCTION AND REASONS FOR USE*

Transparent high lead and tin-opacified lead-alkali glazes have been extensively used throughout Europe and the Near East from their first appearance in the Roman era and the tenth- to eleventh-century Islamic world, respectively, up until the present day. Using, to a large extent, information which is widely scattered through a diverse range of literature, the methods employed in the production of these two glaze types are first outlined and their merits are then compared with those of alkali glazes in terms of ease of preparation of the glaze mixture, ease of application of the glaze, ease of firing, cost of production, glaze-body fit and visual appearance. The principal advantages of transparent high lead glazes as compared to alkali glazes are shown to be ease of preparation and application of the glaze suspension, low susceptibility to glaze ‘crazing’ and ‘crawling’ and high, optical brilliance. Factors that influence the choice of tin-opacified lead-alkali glazes include ease of production of tin oxide by melting tin and lead metals together; a reduced risk of reduction of lead oxide to lead metal and consequent blackening of the glaze; and, again, low susceptibility to ‘crazing’ and ‘crawling’. Limits of current knowledge regarding these two glaze types and requirements for future research are outlined.