THE HISTORY OF THE LAWRENCE BERKELEY NATIONAL LABORATORY INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS PROGRAMME FOR ARCHAEOLOGICAL AND GEOLOGICAL MATERIALS

The Lawrence Berkeley National Laboratory pottery provenance group developed standards and instrumental neutron activation analysis (INAA) methods that are used at many archaeometry laboratories around the world. The background and development of ‘Standard Pottery’ and of methods for INAA are described. Early pottery provenance studies are described, and other research programmes, involving obsidian and magmatic mixing, the origin of the stone used for the Colossi of Memnon, and the ‘Plate of Brass’, are mentioned. Research work by the Laboratory included the discovery of the world‐wide iridium anomaly and extensive subsequent research on what has come to be known as the ‘Asteroid Impact Theory’. Characteristics of the analytical programme for pottery provenance work, including overall aims, precision and accuracy, intercalibration, and irradiation and measurement protocols, are discussed. New research areas developed in the past 15 years, to broaden the usefulness of chemical compositional data for archaeological investigation, and examples of recent work, are described. This research, which makes use of high‐precision X‐ray fluorescence analysis in addition to INAA measurements on sample splits, includes distinguishing the products of different workshops located at the same production site, studies on the significance of the distribution of silver in archaeological pottery and the use of high‐precision chemical compositional data as an aid for making chronological distinctions.     

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 Endeavours to preserve unpublished results are described.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.     

NEUTRON ACTIVATION ANALYSIS OF INCA AND COLONIAL CERAMICS FROM CENTRAL HIGHLAND ECUADOR

Fifty‐three ceramic samples were collected in the area of the colonial city of Riobamba, Ecuador (today Sicalpa/Cajabamba). Neutron activation analysis was used to attempt to establish elemental compositions, and from these gain information on the manufacturing locations of these samples. Colonial samples imported from Panama were separable by their high Cs contents, and can be sorted into glazed and unglazed industries based on As and Cs. High As concentrations in several sherds indicate an origin near Cuenca, in the Southern Highlands of Ecuador, for both colonial and Inca samples. Inca and colonial Quito samples from the north of the country are identifiable through high Na combined with low Sc and Cr concentrations. Locally produced Puruhá, unglazed colonial and majolica samples form a group indicative of local Riobamba elemental composition.     

NEUTRON ACTIVATION ANALYSIS OF BIRD BOWLS AND RELATED ARCHAIC CERAMICS FROM MILETUS

In this paper we present the results of a chemical investigation by neutron activation analysis of sherds of different kinds of bird kotylai, bird bowls and related wares excavated in Kalabaktepe, a hill of the ancient city of Miletus. A new archaeological classification of this well-known group of Archaic ceramics of eastern Greece is presented. A number of kiln wasters of misfired vessels from Kalabaktepe revealed a characteristic local pattern. This pattern helped to clarify the provenance of some of the bird bowls classified archaeologically as of orientalizing type: they have been made in Miletus. But bird kotylai and bird bowls in the 'standard fabric’as well as other archaeologically related vessels show a different chemical pattern of unknown provenance.     

NEUTRON ACTIVATION ANALYSIS OF ARCHAEOLOGICAL MATERIALS: AN OVERVIEW OF THE ITN NAA LABORATORY,PORTUGAL

Instrumental neutron activation analysis (INAA) has been applied to archaeological samples at the Portuguese Research Reactor (RPI) since 1973, and the number of samples analysed has increased steadily since the mid‐1990s. Archaeometric applications of INAA at RPI include the analysis of archaeological ceramics and the stones used in monumental architecture (menhirs) and other historical monuments. A programme of analysis also exists for measuring the precision of and contributing to the certified values of geochemical reference samples. In addition, the study of interference factors is performed to obtain better accuracy in the determination of concentrations of some elements (e.g., corrections for spectral interferences from uranium fission products in the determination of barium, rare earth elements and zirconium).     

NEUTRON ACTIVATION ANALYSIS OF COLONIAL CERAMICS FROM SOUTHERN HIGHLAND ECUADOR*

Sixty‐one ceramic samples collected in Cuenca, Ecuador, were analysed by neutron activation analysis in an attempt to establish their elemental compositions. The bulk of the samples were manufactured in the region of Cuenca, with others imported from Quito in the northern highlands of Ecuador, from Panama Vieja in Panama, and from Seville in Spain. Relative to the Cuenca ceramics, the Spanish samples were separable primarily by their high Ca contents; the Panamanian ceramics by their high Cs contents; and the Quito ceramics by their high Na contents. The ceramics made within the region surrounding Cuenca are much more difficult to separate, with Ba and other elements being potentially important.     

NEUTRON ACTIVATION ANALYSIS OF FAIENCE BEADS

A selection of faience beads has been examined using neutron activation analysis, with a view to distinguishing the provenance of individual specimens. Evidence is presented that the tin content in beads from British sites is significantly higher than in those from other areas. Characteristic features of beads from other sources are also discussed.     

GEOMETRICAL FACTORS IN THE NEUTRON ACTIVATION ANALYSIS OF ARCHAEOLOGICAL SPECIMENS

In the neutron activation analysis of museum specimens, for which sampling is not permitted, corrections must be applied to measured activities to take into account the sample shape and its position relative to the detector. Correction factors are derived for samples of cylindrical shape such as segmented faience beads and a model technique is suggested for those of irregular shape such as flint and obsidian implements. These techniques used in gamma-ray spectrometry with lithium-drifted germanium detectors enable elemental concentrations to be determined from the measured count rates.     

NEUTRON ACTIVATION ANALYSIS OF CERAMICS: PROBLEMS WITH TITANIUM AND CALCIUM

Titanium and calcium in ceramic materials can be analysed by neutron activation using a number of radioisotopes. Historical usage of scandium-47 for the analysis of both elements is reviewed. Measurements were made of the production and decay of ⁴⁷Sc sources prepared by SLOWPOKE reactor irradiations of pure titanium and calcium salts. Relative interferences were established and their effects calculated for a range of ceramic types. This study indicates that published values of the concentrations of titanium and calcium, using ⁴⁷Sc, must be seriously reassessed.     

NEUTRON ACTIVATION ANALYSIS OF SIXTEENTH- AND SEVENTEENTH-CENTURY EUROPEAN BLUE GLASS TRADE BEADS FROM THE EASTERN GREAT LAKES AREA OF NORTH AMERICA*

Sixteenth- and seventeenth-century European blue glass trade beads from aboriginal sites in the eastern Great Lakes area of North America have been analysed non-destructively using low neutron dose instrumental neutron activation analysis, so that the beads could be returned to their keepers. Dark blue (cobalt-coloured) beads are readily separable from turquoise (copper-coloured) beads. Differences in the chemistries of the turquoise blue beads appear to be useful in separating glass beads from the two centuries. Low calcium, sixteenth-century turquoise beads tend to distintegrate by a leaching of the alkali metals.