LEAD ISOTOPIC EVIDENCE FOR A MIXED PROVENANCE FOR ROMAN WATER PIPES FROM POMPEII*

Lead isotope analysis has been applied to the investigation of some Roman objects found in the town of Pompeii, consisting mostly of fistulae from the Augustan water supply system. The results of the analyses have produced ratios between 18.10 and 18.66 for ²⁰⁶Pb/²⁰⁴Pb, between 15.63 and 15.72 for ²⁰⁷Pb/²⁰⁴Pb and between 38.21 and 38.98 for ²⁰⁸Pb/²⁰⁴Pb. These data point to a fairly complex origin for the lead artefacts, probably involving several successive meltings and recyclings of a rather heterogeneous lead supply. The spread of lead isotope ratios can only be reconciled with a multiplicity of end‐members, at least three, but very probably more. There is one certain Sardinian ore, other indistinguishable Hercynian ores of Sardinia and/or Spain, and several different Alpine Mesozoic‐Tertiary mineralizations of the Mediterranean basin (Spain, Greece, Tuscany).     

MULTI‐METHOD MARBLE PROVENANCE DETERMINATIONS: THE CARRARA MARBLES AS A CASE STUDY FOR THE COMBINED USE OF ISOTOPIC,ELECTRON SPIN RESONANCE AND PETROGRAPHIC DATA*

A multi‐method approach, based on petrography, stable isotope data and electron spin resonance spectroscopy for assigning the provenance of white marbles, is presented. A total of 11 experimental variables has been used, including the quantitative measurement of the sample colour and its homogeneity. On this basis we attempt to distinguish the three main quarrying basins of the Carrara district, that is, Torano, Miseglia and Colonnata. Such discrimination, extremely uncertain on the basis of the single techniques, may be performed with acceptable confidence’ using a properly selected subset of six petrographic, isotopic and spectroscopic variables. The final resubstitution and jackknifed re‐assignment rates are, respectively, 85% and 81%. Inclusion of the remaining five variables into the classification rule does not improve the results, but simply increases data overinterpretation. The practical possibility of using such an approach for more general provenancing problems is considered.     

DIRECT EVIDENCE OF PRIMARY GLASS PRODUCTION IN LATE BRONZE AGE AMARNA,EGYPT

This paper presents direct archaeological evidence for the primary production of glass at the LBA site of Tell el‐Amarna, in the form of numerous finds of semi‐finished glass. The diagnostic microstructural and chemical composition of these finds is presented alongside macroscopically similar finds, of shapeless lumps of finished white glass. The semi‐finished glass was found to contain numerous inclusions of residual quartz and newly formed lime‐rich crystal phases, but no added colorant. However, several samples of semi‐finished glass have antimony oxide levels comparable to those of finished white glass, suggesting that the opacifier was added to the initial glass‐making batch. The results are discussed in comparison with the evidence for glass‐making from Qantir – Pi‐Ramesse, identifying some close technical similarities, which indicate that the same technological processes were used at both sites for the production of glass.     

PHYSICO‐CHEMICAL CHARACTERIZATION OF THE ACQUALADRONE ROSTRUM

The archaeological discovery of the Acqualadrone rostrum (an offensive naval weapon mounted on the prow at the waterline), off the Italian coast near Messina in 2008, has led to the need for scientific research in order to plan the conservation treatment of this artefact. The discovery is exceptional because of the presence of a wooden section from the original ship. This paper describes the physico‐chemical characterization of a metallic and two wooden samples by inductively coupled plasma – optical emission spectroscopy, inductively coupled plasma – mass spectrometry, Fourier transform infrared spectroscopy, ¹³C {¹H} cross‐polarization magic angle spinning NMR spectroscopy, energy‐dispersive X‐ray spectroscopy, gas chromatography – mass spectrometry and X‐ray diffraction. The results reveal the use of leaded bronze (Cu, 70%; Pb, 20%; Sn, 10%) in the manufacturing process of the alloy and the use of lead whose isotopic composition is referable to either Spanish or Cypriot mines. The analysis of the results relating to the wooden samples indicates their different state of preservation and, at least in some places, the spreading of caulking on the wood, probably using a vegetable resin.     

CLAY RESOURCES AND TECHNICAL CHOICES FOR NEOLITHIC POTTERY (CHALAIN,JURA, FRANCE): CHEMICAL,MINERALOGICAL AND GRAIN‐SIZE ANALYSES*

Many authors have considered pottery manufacturing constraints and sociocultural elements as factors in change in past civilizations over time. The main issue of this research is to better understand the reasons for changes, or choices, in pottery raw materials. The very precise and detailed stratigraphy and cultural succession of occupations is based on dendrochronological data from the lake‐dwelling sites of Chalain (Jura, France). Petrographic, palaeontological and chemical analyses were used to determine the nature and origins of the raw materials used by the Neolithic potters. Stratigraphy and dendrochronological data were used to reconstruct in detail the evolution dynamics of fabric changes. Several raw material sources were identified for many of the pottery groups. Each of them was sampled for qualitative experimental tests of pottery forming. The experimental results show a high variability between the sediments tested. This variability was quantitatively estimated by XRF, XRD, the Rietveld method, calcium carbonate quantification and laser grain‐size analyses of matrices, indirect measures of plasticity. These analytical results allow a better understanding of the differences observed in the experimental tests. On the basis of these experimental and analytical results, changing parameters such as pottery manufacturing constraints, mineralogical characteristics of raw materials and sociocultural factors are considered. In conclusion, all the social and technical parameters, in each archaeological context, must be taken into account for a better understanding of the changes occurring throughout the chronological sequence.     

INSTRUMENTAL NEUTRON ACTIVATION BASED PROVENANCE STUDIES AT THE HEBREW UNIVERSITY OF JERUSALEM,WITH A CASE STUDY ON MYCENAEAN POTTERY FROM CYPRUS

A neutron activation programme aimed at archaeological provenance research operated at The Hebrew University of Jerusalem between the years 1974 and 1997. The history and accomplishments of that laboratory are presented. Endeavours to preserve unpublished results are described. Results on Cypriote pottery are presented.     

MULTIVARIATE MIXTURE OF NORMALS WITH UNKNOWN NUMBER OF COMPONENTS: AN APPLICATION TO CLUSTER NEOLITHIC CERAMICS FROM AEGEAN AND ASIA MINOR USING PORTABLE XRF*

Multivariate techniques and especially cluster analysis have been commonly used in archaeometry. Exploratory and model‐based techniques of clustering have been applied to geochemical (continuous) data of archaeological artefacts for provenance studies. Model‐based clustering techniques such as classification maximum likelihood and mixture maximum likelihood have been used to a lesser extent in this context and, although they seem to be suitable for such data, they either present practical difficulties—such as high dimensionality of the data—or their performance gives no evidence that they are superior to standard methods. In this paper standard statistical methods (hierarchical clustering, principal components analysis) and the recently developed model‐based multivariate mixture of normals with an unknown number of components, are applied and compared. The data set provides chemical compositions of 188 ceramic samples derived from the Aegean islands and surrounding areas.     

THE GEOCHEMISTRY OF THE MAJOR SOURCES OF ARCHAEOLOGICAL OBSIDIAN ON HOKKAIDO ISLAND (JAPAN): SHIRATAKI AND OKETO

The geochemical compositions for obsidian from two of the most important sources on the Japanese island of Hokkaido, Shirataki and Oketo, are presented. This work represents the first systematic study of obsidian geochemistry on Hokkaido from the view of modern methodological standards. The study was performed with the help of neutron activation analysis to determine the concentrations for 28 elements. The results obtained allow us to subdivide both sources into two geochemical groups (Shirataki‐A and ‐B; and Oketo‐A and ‐B), with each representing an individual sub‐source. Obsidian from both Shirataki and Oketo sources is identified at archaeological sites located on Hokkaido, on the neighbouring Sakhalin Island and Kurile Islands, and in the lower course of the Amur River basin. The distance of obsidian transport during the Upper Palaeolithic was up to ～250 km, and in the following Neolithic and Palaeometal periods up to ～1200 km. This testifies to the wide distribution of Hokkaido obsidian to archaeological complexes in North‐East Asia and its active transport/exchange in prehistory. The data presented here should be used as a reference for the obsidian geochemistry of Shirataki and Oketo sources from now on.     

MEDIEVAL LEAD GLASS IN CENTRAL EUROPE

In Trommsdorfstraße, Erfurt, a glass‐processing workshop has been excavated, which produced lead glass rings and beads in the 13th century. This workshop produced two different lead glasses. The first, a high‐lead glass, could be found throughout Europe, from England to Russia. However, another newly defined type of glass could be identified (Central European lead–ash glass). This can be demonstrated by analysing the literature, and it has been found in eastern Germany, Poland, Slovakia and the Czech Republic. A Slavic lead–ash glass with the same ash content as the Central European lead–ash glass but lower amounts of lead was produced in Eastern Europe. In western Germany, another type of ash (beech ash) was used to produce a wood‐ash lead glass. Lead‐isotope analysis proved that the same source of lead was used for the wood‐ash lead glass and the high‐lead glass in western Germany and the two types of glass from Erfurt.