ARCHAEOMETRY AND MUSEUMS: FIFTY YEARS OF CURIOSITY AND WONDER*

Artefacts and works of art kept in museum collections originated in many cases from ancient private collections. In such cases, a partial or total absence of historical information may create additional problems concerning their authenticity. The study of museum collections and their preservation requires the use of analytical techniques but also combined examination techniques not commonly necessary for the study of archaeological objects. This paper gives an overview of the importance of museum items for the understanding of the past, the difficulties relating to their authentication and the significant advances brought about by science‐based techniques, in particular those cases discussed in Archaeometry during the past 50 years.     

The circulation of precious metals in the Arab Empire: the case of the near and the Middle East*

The analysis by nuclear activation techniques and by inductively coupled plasma mass spectrometry combined with an UV laser of a large number of gold coins issued in the Arab Empire from the seventh to the 12th century ad showed that several different supplying sources were used, according to the region and to the period. The aim of this paper is to point out the circulation of gold in the Near and Middle Eastern mints of the Arab Empire and to make a parallel with the mints’ policies running in the other regions of the Empire, such as North Africa, the Iberian Peninsula and the Sicily. The identification of different gold ores by means of characteristic trace elements indicated recycling of the ancient coinage and, after ad 750, the minting in the entire Arab Empire of different new gold ores: Egyptian type, North Eastern type and West African type. The analysis of a small number of silver coins from the same periods and regions also showed a change in the ore supply after ad 750.     

X-RAY FLUORESCENCE CHARACTERIZATION OF THE CORONA FERREA*

X-ray fluorescence (XRF) analyses of metals, glasses and enamels from the Corona Ferrea, or Iron Crown, of Monza are reported. The method followed to obtain quantitative analysis of metal alloys was based on comparison with standards and it is framed on the more general problem of XRF quantitative analysis of irregularly shaped objects with a portable instrument. Preliminary radiocarbon dating results are also reported.     

HUMAN MOBILITY AT THE EARLY NEOLITHIC SETTLEMENT OF VAIHINGEN,GERMANY: EVIDENCE FROM STRONTIUM ISOTOPE ANALYSIS*

As evidence concerning human mobility during the transition to agriculture in central Europe, we present the results of strontium isotope analysis of human skeletons from the Neolithic village of Vaihingen, Germany. We find significantly more ‘non‐local’⁸⁷Sr/⁸⁶Sr values from humans buried in a Neolithic ditch surrounding Vaihingen than from those buried within the settlement. These results fit with previous studies showing a correlation between burial circumstances and strontium isotope signatures from LBK cemeteries of southwestern Germany ( Price et al. 2001 ; Bentley et al. 2002 ). A pilot study of Neolithic animal teeth from Vaihingen suggests that either ‘local’⁸⁷Sr/⁸⁶Sr signatures were more variable than the analysed human bones suggest, or that these domestic animals themselves were mobile, perhaps ranged by mobile pastoralists.     

NEUTRON TOMOGRAPHY AS A VALUABLE TOOL FOR THE NON‐DESTRUCTIVE ANALYSIS OF HISTORICAL BRONZE SCULPTURES

This paper explains, with the example of a Roman object (the ‘Mars from Oberweningen’, Switzerland), why neutrons can be used preferentially for the non‐destructive analysis of metallic objects of relatively large size. This method is superior to the conventional X‐ray tomography method due to the higher penetration ability in metals such as copper, tin and even lead. With this method, differing materials can also easily be differentiated. In this way, the inner and outer structures of objects can be observed with the help of tools based on mathematical algorithms. Slices at arbitrary positions and segmentation of different material clusters aid the understanding of manufacturing processes and can describe the present preservation status. This helps in selecting optimal and additional conservation measures in museums for further preservation. Beside the qualitative overview on structure and inner properties of the objects, quantitative information can be derived about material content and composition. This method and the subsequently needed facilities for this method are available at PSI for similar studies on demand.     

PETROGRAPHY AND PROVENANCE INTERPRETATION OF THE STONE MOULDS FOR BRONZE DAGGERS FROM THE GALDONG PREHISTORIC SITE, REPUBLIC OF KOREA*

This paper presents material characteristics and raw material provenance of the stone moulds for bronze slender daggers from Galdong. This type of bronze dagger is uniquely distributed in the Korean Peninsula and these stone moulds were the first to be found by excavation. The stone moulds were made of igneous hornblendite with course-grained holocrystalline textures. Based on petrological, mineralogical and geochemical characteristics, the original rock materials of the moulds were inferred to be derived from the Jangsu or Namwon areas which are about 50 km away from the excavation site. It is a notable achievement that this provenance study confirmed the domestic production of Korean-styled daggers.     

DETECTING CHANGES OF CELTIC GOLD SOURCES THROUGH THE APPLICATION OF TRACE ELEMENT AND Pb ISOTOPE LASER ABLATION ANALYSIS OF CELTIC GOLD COINS*

This project follows on from an initial study of Celtic gold coins from the Middle Rhine/Moselle region, which was based on material found at the Martberg, a Late Iron Age/Roman sanctuary and settlement (River Moselle, western Germany; Bendall 2003 ). The earlier work was expanded to encompass over 100 examples of various other regional Celtic gold coinages from the collection of the Römisch‐Germanisches Zentralmuseum, Mainz. The alloy (Au–Ag–Cu) and trace element compositions (in particular Ni, Sb and Pt) were determined by EPMA and LA–ICP–MS, respectively, and their Pb isotope signatures were measured by LA–MC–ICP–MS. Of the 28 trace elements measured, only Ni, Sb and Pt were found to show meaningful variations and so only they are presented here. In particular, differences in the Pt/Au ratios between various groups of earlier coinage (imitations of Philippus and Alexander/Nike staters, Sch. 23 and some early Boian coins) on the one hand, and the majority of the Boian and the southern rainbow cup coinages on the other, indicate a significant difference in the gold sources exploited for these regional coinages. The Pb isotope data confirm previous conclusions that the contribution of gold to the total lead in the Au–Ag–Cu coin alloys can be detected, especially for coins with over 70% gold, and show that possible gold sources include both eastern Mediterranean and Alpine sources. Combining the Pb isotope data with the Pt/Au ratios allows the potential gold sources to be further differentiated.     

HANNIBAL GONE ASTRAY? A CRITICAL COMMENT ON W. C. MAHANEY ET AL.: ‘THE TRAVERSETTE (ITALIA) ROCKFALL: GEOMORPHOLOGICAL INDICATOR OF THE HANNIBALIC INVASION ROUTE’ (ARCHAEOMETRY, 52, 1 [2010] 156–72)

For a long time now, historians have considered the way across the Col de Clapier as the most likely invasion route of Hannibal's army across the Alps. Mahaney et al. challenge this view by introducing a two‐tier rockfall into the discussion, which they believe is mentioned in the ancient texts and has gone unnoticed by modern scholars. Since a deposit of this kind can only be found at the Col de la Traversette—and there alone—Hannibal's crossing of the Alps, so they reason, must have followed this alternative route. However, a critical reassessment of the ancient texts and a closer look at the geomorphological situation clearly show that this interpretation is unwarranted.     

INVESTIGATING SEASONALITY AND SEASON OF BIRTH IN PAST HERDS: A REFERENCE SET OF SHEEP ENAMEL STABLE OXYGEN ISOTOPE RATIOS

Intra‐tooth sequential analysis of enamel δ¹⁸O is currently used to investigate birth seasonality in past animal populations, offering new insights into seasonal availability of animal resources, herd management and seasonality of site occupation. Reference data sets are still required to address two major difficulties: (1) that inter‐individual variability in the record of the seasonal cycle is affected by tooth size; and (2) that the season of birth cannot be directly estimated from the timing of tooth growth, because of a delay in enamel mineralization. We present a data set acquired on the lower second molar of 10 modern sheep from Rousay (Orkney) born within a few weeks of each other in April/May and submitted to the same environmental conditions until death. All sheep have recorded a sinusoidal pattern of δ¹⁸O variation spanning approximately a year. From the difference between the expected and the measured time sequence, the delay of enamel mineralization is estimated to be 5–6 months. The data set is then described using a model mainly based on a cosine function. The period, corresponding to the length of the M2 crown formed over a year, averaged 35.8 mm. A very slight variation of tooth growth rate with time and no attenuation of the isotopic signal towards the cervical margin of the crown could be detected in this data set. The lowest δ¹⁸O values, corresponding to the sheep's first winter, were tracked at a distance from the enamel/root junction that varied between 23.0 and 30.3 mm (x_min mean = 27.6 mm); the highest δ¹⁸O values, corresponding to the sheep's second summer, were between 6.3 and 11.6 mm (x_max mean = 9.9 mm). Most of the variability can be attributed to tooth size. When normalized on the period, x_min and x_max are 0.28 (± 0.05) and 0.78 (± 0.05) on average, meaning that the Rousay sheep have recorded the minimum and maximum δ¹⁸O values on average at 78% and 28%, respectively, of the end of the periodic cycle recorded in the second molar.     

NO STONE UNBURNED: A COMPOSITIONAL ANALYSIS OF OBSIDIAN MICRODEBITAGE BY LASER ABLATION TOF–ICP–MS

Obsidian is an effective material for the study of prehistoric raw material use and exchange, due to the high degree of homogeneity and redundancy of obsidian materials and manufactured objects in the archaeological record. The destructive nature of many analytical techniques often impedes compositional research because of the damage that may occur to priceless archaeological artefacts. The combination of time‐of‐flight (TOF) ICP–MS with a laser ablation sample introduction system provides a highly efficient means of chemically characterizing obsidian. This study shows that sample size limit capabilities of TOF–ICP–MS analysis of obsidian can reach less than 100 μm. Sampling and analysis of microartefacts enables researchers to overcome problems of sampling bias with very little damage to the valuable existing materials within the archaeological record and expands the potential for chemical compositional analyses in archaeology.