Aspects of the Production of Cobalt‐blue Glass in Egypt

Cobalt‐blue glass of the Near and Middle Eastern Late Bronze Age has long been recognized as compositionally distinct from other contemporary glasses (Sayre 1967; Lilyquist et al. 1993). It has been suggested recently by Shortland and Tite (2000) that this chemical distinction reflects the use of Egyptian raw materials for making these glasses, different from those used to make glass in Mesopotamia, or its manufacture by Mesopotamian workmen, possibly in Egypt. This assumed that cobalt‐bearing alum from the Western Oases and mineral natron from the Wadi Natrun were used for the cobalt‐blue glass, while the other, probably Mesopotamian, glasses were made using plant ash as the main alkali source. This note discusses some technical aspects of the possible ways in which the cobalt could have been added to the glass, and how this relates to the likely raw glass used in its making. Combining earlier suggestions by Noll (1981) and Brill in Lilyquist et al. (1993), an alternative explanation of the chemical characteristics is suggested, maintaining that all the glasses under discussion were made using plant ash. Differences in alkali concentrations probably reflect different soil and plant chemistries, and the colorant was probably added to the glass after being precipitated from the alum as a complex cobalt aluminium hydroxide.     

The Possibility of Provenancing A Series of Bronze Punic Coins Found At Tharros (Western Sardinia) Using the Literature Lead Isotope Database

A sample set of 42 bronze Punic coins dating from the third century bc and excavated in the Phoenician, Punic and then Roman town of Tharros (western Sardinia) has been used to test the performance of the literature lead isotope database and to establish a well defined provenancing procedure. A selection from the available database, including Cypriot, Sardinian and Spanish ore deposits, has been used. The complete assignment has been carried out twice, using both statistical methods (linear discriminant analysis) and the conventional raw data plots. Three major and one minor disagreements have been found, suggesting that the two procedures, when properly employed, may be acceptably compatible. Almost one third of the coins exhibit a characteristic Cypriot signature, whereas only very few samples are compatible with Sardinian ores. However, the majority of the coins (c. 60%) cannot be associated with any known source, which suggests the possibility of extensive metal recycling.     

LUMINESCENCE DATING OF POTTERY FROM LATER PREHISTORIC BRITAIN*

Dating of later prehistoric settlements relies heavily on potter; typologies in England and yet there has been little scientific dating in order to verify these typologies. In this work, luminescence dating techniques were applied directly to the pottery which forms the typological framework. Excellent agreement was obtained between the luminescence ages, and archaeological age ranges for known‐age pottery sherds with diagnostic form and surface decoration. A lower correlation, however, was found in several regions between the luminescence ages for undecorated body sherds and the archaeological assessment which was necessarily based solely on fabric, suggesting the need for reassessment of these fabric chronologies.     

THE ORIGIN OF THE PICTORIAL KRATER FROM THE ‘MYCENAEAN’ TOMB AT TEL DAN

A Late Bronze Age Mycenaean pictorial krater, decorated with a chariot procession, from tomb 387 at Tel Dan, Israel, was examined by instrumental neutron activation analysis. The origin of the krater is placed in the Argolid, very likely in the region of Mycenae or Berbati.     

STATISTICAL EVALUATION OF THE PRESENTLY ACCUMULATED LEAD ISOTOPE DATA FROM ANATOLIA AND SURROUNDING REGIONS

Several hundred new stable lead isotope ratio determinations of ore and slag specimens from ancient mining sites throughout Anatolia and of samples of artefacts of the Chalcolithic, Bronze Age and Early Iron Age from museum collections in Turkey and the United States have been combined with the accumulated published isotope determinations of such specimens from throughout the eastern Mediterranean and Aegean regions to form a data base of nearly 1000 analyses. It is the purpose of this paper to evaluate the practical effectiveness of using this now extensive data base to discriminate between the many sources of metals throughout this region and to propose methods to enhance this discrimination. By using the full three-dimensional isotopic data in multivariate statistical treatments and by separating isotopically resolvable source groups within some of the source areas and isolating statistically outlying specimens from them, it has been possible to characterize some ore sources more precisely and compactly and thereby achieve better resolution between ore sources. It has also been possible to isolate isotopically compatible artefact groups which possibly relate to ore sources that, as yet, have not been well defined by isotopic analysis.     

EARLY BRONZE AGE TIN PROCESSING AT KESTEL/GÖLTEPE,ANATOLIA

Chemical analysis of statistically significant numbers of samples including minerals, sediments, soil, host rock as well as powdered materials, crucible accretions and metal artefacts revealed information about the distribution of cassiterite at Kestel and the tin smelting processes that took place at Göltepe c. 2600 BC. Using the ancient technique of vanning for the isolation of tin ore (cassiterite), followed by assaying by blowpipe/charcoal block, as well as crucible smelting with a blowpipe, good tin metal suitable for alloying with copper to make bronze was obtained. There is every indication that tin was mined and smelted in the Early Bronze Age at the Kestel/Göltepe sites.     

CHARACTERIZATION AND THERMOLUMINESCENCE DATING OF PREHISTORIC POTTERY SHERDS FROM MILENA

This paper reports the results obtained applying absolute dating methodologies and mineralogical, petrographical and micropalaeontological characterization techniques to prehistoric pottery sherds varying in age from the Sicilian Middle Neolithic to Bronze Age. All samples came from the archaeological area of Milena (Caltanissetta, Sicily); those of the Bronze Age were found on a site with a precise stratigraphic succession. The investigation has contributed to the determination of an absolute chronology for the Milena prehistoric period. The data provide, for the first time in Sicily, absolute dates covering a wide spectrum of cultures following one another in the same area and, for the Bronze Age site, correlated to the precise stratigraphic succession. The petrographical and mineralogical analyses allowed not only the identification of the principal constituents of the pottery, but also the formulation of some hypotheses regarding the specific manufacturing techniques of different epochs. The microfacies, obtained from the presence of fossils in the groundmass of the pottery, were also analysed and compared with the microfauna present in the Miocene clays outcropping in the area. The data identified local Messinian clay as the raw material probably used in the manufacture of the pottery and also support the presence, already assumed by archaeologists, of imported Mycenaean pottery, thus supporting the dates obtained on pottery taken from the same stratum.     

LEAD ISOTOPE CHARACTERISTICS OF THE CYPRUS COPPER ORE DEPOSITS APPLIED TO PROVENANCE STUDIES OF COPPER OXHIDE INGOTS

Nearly 200 new lead isotope analyses of sulphidic and oxidized ores from 26 copper mines on Cyprus show that the mines from different geological regions group in five distinctive isotopic groups, each with a substructure, related to the geological history of the ore formation. Comparison of lead isotope compositions of Bronze Age artefacts with these data can in many cases reveal the actual mines from which the copper for particular artefacts was obtained. The particular case of the provenance of the copper for 78 Late Bronze Age copper ‘oxhide ingots’found in Cyprus, Crete, Greece, Sardinia, Turkey and Bulgaria is discussed. The data show that all oxhide ingots so far analysed, dating to the fourteenth century BC and later, were made of copper consistent isotopically with only one mining region in the geographical north of Cyprus, and especially the Apliki mine. The study provides further evidence which supports the validity of the conventional approach to the use of lead isotope analysis for provenancing metals; this evidence is antithetical to recent suggestions of a model for the production of copper oxhide ingots which involved widespread mixing of copper from a number of ore sources throughout the Mediterranean.     

A NEW SETTING FOR THE NORTHERN BORDER OF THE VENETI: METALLIC FINDS FROM THE VENETIC SITE OF MONTE CALVARIO,AURONZO DI CADORE*

In 2000 several bronze and lead objects were discovered at the Venetic‐Roman site (200 bc –ad 200) of Monte Calvario di Auronzo, in the Italian eastern Alps. They were mostly finished artefacts plus semi‐worked products. Analysis included SEM–EDS, EMPA, XRPD, TMS and AMS spectrometry. The compositional results of the finished artefacts suggest that the choice of the alloy had been made according to the decorative techniques to be used. A semi‐worked high‐leaded bronze object indicates the existence of a metallurgical production of cast artefacts at the site. TMS analyses of a lead ingot exclude local provenance, proving the existence of important trade routes.     

TIN ISOTOPY—A NEW METHOD FOR SOLVING OLD QUESTIONS

Tin was a vital commodity in times past. In central Europe, the earliest finds of tin‐bronze date to about 2200 bc , while in Greece they are c. 400–500 years earlier. While there is evidence for prehistoric copper mining—for example, in the Alps or mainland Greece, among other places—the provenance of the contemporary tin is still an unsolved problem. This work deals with a new approach for tracing the ancient tin via tin isotope signatures. The tin isotope ratios of 50 tin ores from the Erzgebirge region (D) and 30 tin ores from Cornwall (GB) were measured by MC–ICP–MS. Most ore deposits were found to be quite homogeneous regarding their tin isotope composition, but significant differences were observed between several deposits. This fact may be used to distinguish different tin deposits and thus form the basis for the investigation of the provenance of ancient tin that has been sought for more than a century. Furthermore, the tin‐isotope ratio of the ‘Himmelsscheibe von Nebra’ will be presented: the value fits well with the bulk of investigated tin ores from Cornwall.