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 WATER ABSORPTION ANALYSIS OF NABATEAN,NORTH AFRICAN AND OTHER CLAY LAMP FABRICS UNEARTHED AT THE RED SEA PORT OF ROMAN AILA (AQABA,JORDAN)*

A water absorption analysis was conducted on 103 clay lamp samples to determine whether the fabrics of this pottery type are porous. If so, this would lend further support to the long‐standing assumption that lamp makers coated their lighting vessels with slip—not just for decorative purposes, but as a means of preventing oil seepage of the fuel chamber. The samples were excavated at the Red Sea port of Roman Aila (modern Aqaba, Jordan) and belong to 10 different types originating from Arabia, Palestine, Egypt, Tunisia and Gaul. The results of the experiment reveal that clay lamp fabrics are porous, and comparatively more so than a reference group of non‐lamp pottery from Pella (Jordan). Petrographic thin‐section analysis of select fabrics confirms the presence of pores, cracks and propagating veins indicative of thermal stress resulting from repeated lamp use. Meandering veins identified in a nozzle fragment were created by the diffusion of vapours, probably originating from the burning lamp oil itself. Ancient lamp makers understood that, given its direct exposure to the extreme temperature of the flame, the nozzle was particularly vulnerable to breakage as a result of thermal shock. A porous lamp fabric, however, helped limit crack propagation, allowing the nozzle and the lamp body to expand and contract to avoid breakage.     

POST-COLONIZATION INTERACTION BETWEEN VANUATU AND FIJI RECONSIDERED: THE RE-ANALYSIS OF OBSIDIAN FROM LAKEBA ISLAND, FIJI*

PIXE–PIGME analysis of 19 obsidian artefacts from Lakeba Island in east Fiji identified contact with northern Vanuatu in the post-colonization period ( c. 2500–1000 bp ) of Fiji. The Lakeba obsidian is the only physical evidence for interaction across the 850 km water gap separating the archipelagos of Vanuatu and Fiji in the first millennium ad . New research on the Vanuatu obsidian sources with laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) casts serious doubt on the validity of a long-distance inter-archipelago connection in the post-Lapita era. This paper presents the re-analysis of 18 obsidian artefacts from Lakeba using LA–ICP–MS and radiogenic isotope results that demonstrate that the Lakeba obsidian is not from Vanuatu, and it most likely derives from the Fiji–Tonga region. Geochemical evidence for long-distance interaction and migration between the West and Central Pacific in the post-Lapita era has yet to be identified.     

CHARACTERIZATION OF LATE CHALCOLITHIC MICRO‐BEADS FROM ÇAMLIBEL TARLASI,NORTH‐CENTRAL ANATOLIA

Micro‐bead manufacture is geographically widespread from the fifth millennium bc . Previous studies of comparable micro‐beads from sites in the Indus Valley region and the Near East suggest that many of these beads were formed from synthetic enstatite. Characterization of micro‐beads from the Late Chalcolithic site of Çaml?bel Tarlas? was carried out by optical microscopy (OM), scanning electron microscopy (SEM) and microanalysis with energy‐dispersive X‐ray spectroscopy (EDS), and X‐ray diffraction analysis (XRD). The chemical composition of the micro‐beads analysed indicated that they were made from three distinctive materials; namely, bulk talc (i.e., synthetic enstatite precursor), apatite and mineral‐rich clay pastes.     

A MULTIDISCIPLINARY APPROACH TO THE CHARACTERIZATION OF ROMAN GRAVESTONES FROM AQUILEIA (UDINE,ITALY)*

The results of an archaeometric study on gravestone production in Aquileia (northeastern Italy) during Roman Republican times are reported here. The artefacts are made of limestone, quarried from the sedimentary sequence of the Trieste Karst (Carnican Alps, northeastern Italy), as testified by historical sources which refer to the ‘Roman Quarry’ at Aurisina. The rock types used for the gravestones are petrographically, geochemically and geochronologically homogeneous, and display similar faunal assemblages. In addition, their age is restricted to the Santonian – Lower Campanian. Comparisons between archaeological finds and rock specimens from various active and inactive quarries in this area suggest that quarrying during Roman Republican times was limited to a specific stratigraphic horizon of the sedimentary sequence, corresponding to the higher part of the ‘Roman Quarry’.     

GEOCHEMICAL PROVENANCE OF OBSIDIAN ARTEFACTS FROM THE MSA SITE OF PORC EPIC,ETHIOPIA*

Obsidian geochemical analysis has become an indispensable tool in archaeological research and has wide applications. However, in spite of the abundance of geological and archaeological obsidian, there has been virtually no such investigation in Ethiopia. Recent instrumental characterization of 31 obsidian artefacts from the Middle Stone Age site of Porc Epic and numerous obsidian geological sources show that artefacts were being transported from as far as 250 km away. We believe this has relevance to the understanding of the emergence of modern human behaviour.     

NEOLITHIC ZOOMORPHIC VESSELS FROM EASTERN MACEDONIA,GREECE: ISSUES OF FUNCTION*

Five fragments of Late Neolithic clay zoomorphic vessels from northern Greece have been analysed for organic residues by gas chromatography – mass spectrometry. The results showed that the containers had been used in connection with a number of substances, in particular lower terpenoids, an oil or fat, possibly fossil fuel and in one case possibly beeswax. The paper considers likely interpretations of such combinations of materials in relation to possible functions of these symbolically enhanced artefacts. It appears that substances may have been used in the vessels because of their aromatic and/or medicinal and combustible properties, possibly in order to produce light, fragrance and/or smoke.     

NON‐DESTRUCTIVE ANALYTIC METHOD USING XRF FOR DETERMINATION OF PROVENANCE OF ARCHAEOLOGICAL OBSIDIANS FROM THE MEDITERRANEAN AREA: A COMPARISON WITH TRADITIONAL XRF METHODS*

A non‐destructive analytical method using wavelength‐dispersive X‐ray fluorescence (WDXRF) that allows the establishment of the provenance of archaeological obsidians was developed and a comparison with the classical XRF method on powders is discussed. Representative obsidian samples of all the geological outcrops of archaeological interest of the Mediterranean area (Lipari, Pantelleria, Sardinia, Palmarola and the Greek islands of Melos and Gyali), were analysed with the normal procedures used in rock analysis by XRF (crushing, powdering and pelletizing). The non‐destructive XRF analysis was instead conducted on splinters taken from the original geological pieces, with the shape deliberately worked to be similar to the refuse usually found at archaeological sites. Since the analysis was conducted on the raw geological fragment, intensity ratios of the suitably selected chemical elements were used, instead of their absolute concentrations, to avoid surface effects due to the irregular shape. The comparison between concentration ratios (obtained by traditional XRF methods) and the intensity ratios of the selected trace elements (obtained from the non‐destructive methodology) show that the different domains of the chemical composition, corresponding to the geological obsidians of the source areas, are perfectly equivalent. In the same way, together with the geological splinters, complete archaeological obsidians, from Neolithic sites, may be analysed and their provenance may be determined. The proposed non‐destructive method uses the XRF method. Due to its sensitivity, low cost and high speed, it is surely an extremely valid instrument for the attribution of the provenance of the archaeological obsidian from Neolithic sites.     

ANALYSING ARCHAEOLOGICAL BASALT USING NON‐DESTRUCTIVE ENERGY‐DISPERSIVE X‐RAY FLUORESCENCE (EDXRF): EFFECTS OF POST‐DEPOSITIONAL CHEMICAL WEATHERING AND SAMPLE SIZE ON ANALYTICAL PRECISION*

Energy‐dispersive X‐ray fluorescence (EDXRF) has been commonly used to determine geological sources of volcanic glass artefacts, but its ability to discriminate between basaltic sources is less developed. We examine the precision and accuracy of non‐destructive EDXRF for basalt artefacts by analysing varying size and weathering characteristics. The experiments identified no appreciable effect in reproducibility or measured composition due to thickness (down to 1 mm) or natural weathering of pre‐contact flake scars for the 17 elements measured in this study. Samples with surface area less than 100 mm², however, show significant variability in measured composition and reproducibility.     

A PRELIMINARY PETROGRAPHIC ANALYSIS OF CYPRIOT WHITE SLIP II WARE*

Samples of Late Bronze Age White Slip II ware from Cyprus were analysed using optical and scanning electron microscopy in conjunction with energy and wavelength dispersive analyse The slip has a novel granular nature and the coarser aggregates are impressed into the outer surface of the body, indicating that it was applied to a moist surface before the vessels were fired. It has a consistent mineral assemblage (Mg‐chlorite + illite‐smectite + sphene + anatase/rutile ± albite) which is very similar to that of hydrothermally altered zones associated with copper orebodies in the Troodos Massif which were mined in antiquity Our analysis suggests that the raw material for the slip was not found at the ground surface, because the alteration assemblage is unaffected by oxidation and copper carbonate or iron staining. It may, therefore, be a by‐product of sub‐surface ore extraction