WHITE LUMPS IN FIFTH- TO SEVENTEENTH-CENTURY AD MORTARS FROM NORTHERN ITALY

Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy.     

EVALUATION OF BINDER/AGGREGATE RATIOS IN ARCHAEOLOGICAL LIME MORTARS WITH CARBONATE AGGREGATE: A COMPARATIVE ASSESSMENT OF CHEMICAL,MECHANICAL AND MICROSCOPIC APPROACHES*

This paper reports on the comparative evaluation of traditional and innovative methods for the investigation of mortar technology. Preliminary results of various approaches to determining the mix proportions in lime mortars with carbonate aggregate are presented. Quantitative analysis was tested on ad hoc prepared mortars of known composition containing carbonate aggregates of different origin (travertine and Bath limestone). Wet chemical methods, manual disaggregation and Digital Image Analysis of thin sections and cross‐sections stained with Alizarin Red S were tested. The advantages and drawbacks of the different approaches are discussed, and applications to the analysis of archaeological mortars and plasters are highlighted.     

ACCESSORY MINERALS AS TRACERS IN THE PROVENANCING OF ARCHAEOLOGICAL MARBLES,USED IN COMBINATION WITH ISOTOPIC AND PETROGRAPHIC DATA*

Thirty‐eight archaeological marbles (Roman and medieval) from Modena and Reggio Emilia (northern Italy) were provenanced using the accessory minerals as tracers and the results were compared with those inferred for the same artefacts using isotope composition and MGS (maximum grain size of calcite grains). The number of inferred possible sources is generally lower when using the mineralogical method, which therefore seems to be suited to marble provenancing.     

CHARACTERIZATION AND PROVENANCE OF LIME PLASTERS FROM THE TEMPLO MAYOR OF TENOCHTITLAN (MEXICO CITY)

In this work, we present the results of the analyses of 20 lime plaster samples taken from the Templo Mayor (Great Temple), the main pyramid of Tenochtitlan (Mexico), the ancient capital of the Mexicas. The samples were analysed to recover information on the mixtures used in the fabrication of the plasters and for the provenance of the raw materials (in particular, limestone) used to make the plasters. The characterization of the samples was done by OM, SEM/EDS, XRF and LA–ICP–MS analyses, while the identification of the provenance of raw materials was done by studying the lumps present in the samples with LA–ICP–MS. The objective of the study was to establish if there was a relationship between changes in the construction techniques employed in the pyramid over time and if there were changes in the provenance of the raw materials. Six different construction phases of this pyramid are analysed, showing the similarities and differences among them, mainly based on differences in the sieving of the aggregates and in the raw materials employed. The provenance studies of the limestone used to make the plasters demonstrated that all the limestone comes from the Tula region.     

SHELL FRAGMENTATION AS A TOOL FOR QUANTIFICATION AND IDENTIFICATION OF TAPHONOMIC PROCESSES IN ARCHAEOMALACOLOGICAL ANALYSIS: THE CASE OF THE CANTABRIAN REGION (NORTHERN SPAIN)

This paper presents a quantification method for archaeological molluscs using fragmentation categories. By employing the data from nine prehistoric sites (13 000 to 5000 bp ; 15 700 to 5700 cal bp ) in Cantabrian Spain (northern Spain), it has been shown that traditional methods, based on one or two anatomical elements, systematically produce a loss in the minimum number of individuals (MNI) that is sometimes significant. This paper also proposes using fragmentation categories in the calculation of the fragmentation index. In addition, based on these indices, a reflection is made on the difficulty involved in associating the amount of fragmentation of the shells with the taphonomic processes that have occurred at the archaeological sites, especially in discerning which agents have caused the fragmentation.     

ARCHAEOLOGICAL AMBERS FROM NORTHERN ITALY: AN FTIR–DRIFT STUDY OF PROVENANCE BY COMPARISON WITH THE GEOLOGICAL AMBER DATABASE*

European geological ambers of five different localities and types, and Italian geological ambers from seven different deposits have been studied with Fourier transform infrared spectroscopy (FTIR) and diffuse‐reflectance infrared Fourier transform (DRIFT). Ambers from several localities have been characterized for the first time. The research aims to create a database of European ambers, containing both FTIR and DRIFT data. The FTIR spectra are easily comparable with the data commonly available in the literature, whereas DRIFT analyses are shown to be more useful to characterize the archaeological finds. The provenance of several archaeological ambers from northern and southern Italy, dating from the Middle Bronze Age to the Iron Age, is assessed on the basis of the developed database. Of the 35 analysed archaeological objects, all but five are composed of Baltic succinite amber.     

A NOVEL APPROACH TO STUDIES OF PREHISTORIC EXPLOITATION OF STONE TOOL MATERIALS USING MATERIAL COMPOSITION,SURFACE MORPHOLOGY,MICROSTRUCTURE AND MECHANICAL PROPERTIES*

For a comprehensive understanding of material exploitation in prehistory, we applied advanced analytical methods to Japanese prehistoric stone tool materials. Compositions, surface morphologies, microstructures and mechanical properties of the primary lithic materials were analysed. As a result of the tests on actual Palaeolithic artefacts, preferential material selection was observed based on composition, structure and other physical properties of the materials. Homogeneous materials composed of a single type of mineral—α‐quartz—were intentionally selected for Palaeolithic tools regardless of the type of rock. These materials unexceptionally present higher hardness and strength. Moreover, materials composed of extremely fine crystal grains of ~0.1 µm in size with highest hardness and strength were selectively used for sharp‐edged blades. These results lead us to the conclusion that quantitative and objective analyses will give us precise information on prehistoric materials, which will enable us to make an analytical approach to the comprehension of prehistoric exploitation of stone materials. This could eventually complement the traditional interpretation of material exploitation based on conventional petrological classifications.     

THE SECTILIA PANELS OF FARAGOLA (ASCOLI SATRIANO,SOUTHERN ITALY): A MULTI‐ANALYTICAL STUDY OF THE RED,ORANGE AND YELLOW GLASS SLABS*

SEM–EDS, EMPA, ICP–MS and ICP–OES were applied to the study of three sectilia panels made of red, orange and yellow glass slabs. In order to determine the chemical state of Cu, XAS was also performed. The results indicate that, with the exception of the red samples, all slabs were made by mixing a siliceous sand with natron. The red slabs show significant compositional differences with respect to K₂O and MgO contents, probably linked to the use of plant ashes as a source of alkali. The red, orange and yellow slabs are coloured by metallic copper, cuprite and Pb antimonates, respectively. The comparison between the chemical composition of the Faragola samples and several glass reference groups did not provide conclusive evidence of provenance.     

THE SECTILIA PANELS OF FARAGOLA (ASCOLI SATRIANO,SOUTHERN ITALY): A MULTI‐ANALYTICAL STUDY OF THE GREEN,MARBLED (GREEN AND YELLOW), BLUE AND BLACKISH GLASS SLABS

Analyses at the Cu–K, Fe–K and Mn–K edge were performed to study the green, marbled (green and yellow), blue and blackish (deep greyish olive green) glass slabs decorating three sectilia panels from the archaeological site of Faragola. Results indicate that all slabs were made by mixing siliceous sand with natron, sometimes probably mixed with small percentages of plant ash. Cu²⁺ and Pb antimonates should be responsible for the opaque green colours. The dark green and yellow portions of the marbled slabs are respectively comparable to the slabs comprising only one of these colours. Cu²⁺ together with Ca antimonates probably produced light blue slabs, whereas cobalt was used to produce dark blue slabs. We consider it possible that the abundance ratio of Fe²⁺/Fe³⁺ and the complex Fe³⁺S^2? would have an effect on the blackish slabs. The contribution of Mn cannot be ascertained even if it could have played a role in darkening glass colour. The comparison between the chemical composition of Faragola samples and several glass reference groups provided no conclusive evidence of provenance; whereas, the presence of a secondary local workshop can be hypothesized.     

GEOCHEMICAL AND ENGINEERING GEOLOGICAL PROPERTIES OF THE VOLCANIC TUFFS USED IN THE ETRUSCAN TOMBS OF NORCHIA (NORTHERN LATIUM,ITALY) AND A STUDY OF THE FACTORS RESPONSIBLE FOR THEIR RAPID SURFACE AND STRUCTURAL DECAY

The geochemical and engineering geological properties of the tuffs used in the rock‐cut cliff tombs of the Etruscan necropolis of Norchia were investigated to evaluate their susceptibility to different weathering agents and confirm their origin. For the first time, materials were characterized by X‐ray powder diffraction (XRD), Fourier‐transform infrared spectroscopy (FT–IR), thermogravimetric analyses (TGA, DGA and DTG), scanning electron microscopy (SEM–EDS) and energy‐dispersive X‐ray fluorescence (ED–XRF), and their different origins confirmed. Tests of material properties indicate that both tuffs are poorly durable, but one of them is less susceptible to weathering. Although tombs made with the more resistant material show limited surface weathering, they undergo severe structural damage because of stress release and plant root infiltration. This, combined with the microclimatic conditions established inside river canyons, can trigger rock falls, leading ultimately to the complete destruction of these tombs.     

ELECTRON BACKSCATTER DIFFRACTION (EBSD): A NEW TECHNIQUE FOR THE IDENTIFICATION OF PIGMENTS AND RAW MATERIALS IN HISTORIC GLASSES AND CERAMICS

Coloured samples of glass and ceramic were selected for EBSD investigation to verify the potential (advantages and limitations) of this technique in the characterization of the raw materials used and the neoformation phases originating from the manufacturing processes. In the case of copper‐bearing red glasses, it was verified that micrometric droplets, residuals of the original copper source, can be ascribed to metallic copper or to a low‐Sn bronze, due to strongly similar lattice parameters. From the same samples, micrometric flakes were identified by EBSD as magnetite and interpreted as residues of the reducing agent used in the production of such red glasses. Further, the technique allowed the pigment responsible for the yellow colouring of some incised slipware to be recognized as bindheimite. In a third case, the black pigment, contained in some Nestorian decorated pottery, was identified as an amorphous phase of Mn oxide. The accurate identification of the colouring particles and other products or materials offered a more precise comprehension of the production technique, period and site of the examined artefacts, together with scientific parameters for the identification of the raw materials, their transformation during the production cycle and an evaluation of the most reliable recipes used for their preparation.     

CHARACTERIZATION OF THE AMPHORAE,STONE BALLAST AND STOWAGE MATERIALS OF THE SHIPS FROM THE ARCHAEOLOGICAL SITE OF PISA–SAN ROSSORE,ITALY: INFERENCES ON THEIR PROVENANCE AND POSSIBLE TRADING ROUTES*

In December 1998, during excavation for the construction of a new building near San Rossore railway station in Pisa, the remains of ancient ships were discovered. These findings have been dated (radiocarbon) to between the end of the 10th century bc and the fifth century ad ( Belluomini et al. 2002 ). Several transport amphorae belonging to the Hellenistic ship, samples of rocks (stone ballast) belonging to ships B, D and the Hellenistic ship, and stowage materials belonging only to ship B have been analysed. The mineralogical and petrographic data of the investigated samples provided information on the possible provenance of the raw materials utilized in the manufacture of the ceramic amphorae, as well as on the provenance of the rock materials found in the ships as ballast and stowage. The compositional data (obtained through XRD, XRF, OM and EPMA) and their statistical analyses suggest that the provenance of the Dressel amphorae belonging to the Hellenistic ship was the Middle Tyrrhenian coast of Italy, and more precisely the area between Tarquinia and Naples, according to the numerous kilns and wine production sites found in this area. The provenance of the volcanic rocks was from southern Tuscany, northern Latium and possibly the Pontine Islands, whereas the intrusive rock possibly comes from the Calabrian–Tyrrhenian coast and/or the Peloritani area. The impure limestones and the dolostone come from southern Tuscany and the Latium coast; the semi‐metamorphic rocks could come from the coast of southern Tuscany, the Tuscan Archipelago or possibly also from the Ligurian coast; only the sample of mylonitized granitoid possibly comes from either the Calabria–Peloritani arc or the Tuscan Archipelago. The stowage materials, consisting of lapilli and scoria of a pyroclastic nature, are sourced from the Neapolitan area. These data might shed some light on the centres of production of the amphorae and of the trading routes followed by the ships, according to the ports of call.     

THE TUNGSTEN AND TIN SIGNATURE OF IRON ORES FROM ELBA ISLAND (ITALY): A TOOL FOR PROVENANCE STUDIES OF IRON PRODUCTION IN THE MEDITERRANEAN REGION

The mineralogy, petrography and major‐ and trace‐element composition of iron ores from Elba Island (Tuscany, Italy), one of the most important iron sources in the Mediterranean area since the first millennium bc , revealed that hematite‐rich ores display prominent enrichments in W and Sn (up to 4950 μg g^?1 and 8400 μg g^?1, respectively). These two elements are hosted by tiny grains of W–Sn mineral phases (ferberite, scheelite and cassiterite) that are disseminated throughout the hematite matrix. A comparison with iron ores from many Italian and European localities (most of which were exploited in ancient times) suggests the uniqueness of the geochemical pattern of Elba Island hematite‐rich ores (i.e., high W and Sn, low Mo and low Cu, Pb and Zn). We suggest that this geochemical signature may represent a new provenance marker not only for discarded ore at smelting/smithing sites, but, possibly, also for metallurgical slag and smelted metal produced in the chaîne opératoire of the iron process.     

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.     

ARTIFICIAL OR NATURAL ORIGIN OF HEMATITE‐BASED RED PIGMENTS IN ARCHAEOLOGICAL CONTEXTS: THE CASE OF RIPARO DALMERI (TRENTO,ITALY)

This study concerns those crystallographic and microstructural features that can provide indications on the actual origin of red pigments based on hematite (Fe₂O₃). The main features of natural and artificial hematite are recalled and used to discuss the results obtained from the characterization of red‐ochre samples coming from the Palaeolithic site of Riparo Dalmeri, a rock‐shelter located in northeastern Italy, dated to 13 000 cal. bp , and notorious for the presence, among the other finds, of red‐painted calcareous stones. Painting and the treatment of leather and hides obtained from the intensive hunting activity were the main uses of the hematite‐based red‐ochres at Riparo Dalmeri. It turns out that hematite was mostly obtained from the thermal treatment of goethite, which, unlike hematite, was and still is widely available in the neighbourhood of the site.     

CHARACTERIZATION OF NATURAL PRODUCTS ON NATIVE AMERICAN ARCHAEOLOGICAL AND ETHNOGRAPHIC MATERIALS FROM THE GREAT BASIN REGION,U.S.A.: A PRELIMINARY STUDY

Although documentary evidence provided by ethnographers makes reference to the source of adhesives, sealants, dyestuffs and medicines used by the communities of the Great Basin, much of it is sporadic and unspecified. However, observations of amorphous deposits surviving on stone tools, ceramics, basketry and wooden artefacts have prompted an investigation of their identity, procurement and use. The aim initially is to study samples from a number of archaeological and ethnographic contexts from the region. Comparative material includes higher plant and insect resins. The study provides a unique opportunity to document use patterns in plant and animal resources in the Great Basin region.     

PROVENANCING FLINT ARTEFACTS WITH ICP–MS USING REE SIGNATURES AND Pb ISOTOPES AS DISCRIMINANTS: PRELIMINARY RESULTS OF A CASE STUDY FROM NORTHERN SWEDEN

Archaeological flint artefacts from the late Mesolithic/early Neolithic site of Vuollerim, northern Sweden, have been geochemically investigated with ICP–SFMS and MC–ICP–MS in search for the geological/geographical origin of the non‐local flint. The Vuollerim flints were compared with reference samples from Denmark (Cretaceous/Tertiary flint) and Russia (Carboniferous flint). Elemental concentrations as well as elemental ratios for REEs and isotopic ratios for Pb and Sr are presented. Significant differences were found between different geological/geographical contexts. Two of the Vuollerim samples can be ascribed a South Scandinavian origin. Possibly also eastern flint is present, although the results are not conclusive in this case.     

ORTHOIMAGE‐BASED DOCUMENTATION OF ARCHAEOLOGICAL STRUCTURES: THE CASE OF A MEDIAEVAL WALL IN PONTEVEDRA,SPAIN

During the completion of the expansion works at the Museum of Pontevedra (Spain), a stretch of about 60 m of the medieval walled enclosure surrounding the historic city centre was discovered. Due to its value as a heritage element, the discovery of this archaeological structure required the implementation of preservation activities and exhaustive documentation so that future generations will be able to know and enjoy this piece of history. This paper presents digital models that reproduce the original structure of the wall using close‐range digital photogrammetry, as well as orthophotos, which thoroughly document the dimensional and textural characteristics of the archaeological site. In addition to analysing the accuracy and validity of photogrammetry in the conservation of archaeological heritage, a methodology of data capture, processing and photogrammetry representation is evaluated.     

MANGANESE STAINING OF ARCHAEOLOGICAL GLASS: THE CHARACTERIZATION OF Mn‐RICH INCLUSIONS IN LEACHED LAYERS AND A HYPOTHESIS OF ITS FORMATION

During the study of a large number of archaeological glass fragments, manganese‐rich inclusions in leached layers were observed in a limited number of cases. This phenomenon occurs only in black‐coloured leached layers. Since the formation mechanism of such manganese‐rich inclusions is still unclear, a combination of several analytical techniques was used in order to investigate this phenomenon and, more specifically, to obtain more information on (a) the composition and morphology of the inclusions, (b) the chemical state of Mn and (c) the 3D morphology of the inclusions. A mechanism that might explain the formation of these inclusions is proposed.     

CHEMICAL CHARACTERIZATION OF TIN‐LEAD GLAZED POTTERY FROM THE IBERIAN PENINSULA AND THE CANARY ISLANDS: INITIAL STEPS TOWARD A BETTER UNDERSTANDING OF SPANISH COLONIAL POTTERY IN THE AMERICAS*

Majolica pottery was the most characteristic tableware produced in Europe during the Medieval and Renaissance periods. Because of the prestige and importance attributed to this ware, Spanish majolica was imported in vast quantities into the Americas during the Spanish Colonial period. A study of Spanish majolica was conducted on a set of 186 samples from the 10 primary majolica production centres on the Iberian Peninsula and 22 sherds from two early colonial archaeological sites on the Canary Islands. The samples were analysed by neutron activation analysis (NAA), and the resulting data were interpreted using an array of multivariate statistical approaches. Our results show a clear discrimination between different production centres, allowing a reliable provenance attribution of the sherds from the Canary Islands.