FRAGMENTATION ANALYSIS OF ANIMAL BONE SAMPLES FROM ARCHAEOLOGICAL SITES

Frequency distributions of the lengths of the bone fragments are plotted for a number of archaeological sites. Down to a certain critical length, the distributions prove to be very similar for all the sites. Below this length, failure to recover fragments during excavation becomes the predominant factor and the frequencies decline. Distributions of diagnostic bones of sheep/goat, pig and cattle are plotted separately and the preferential recovery of the bones of larger animals is demonstrated. A method is suggested for using data from water-sieved sites to estimate and correct the effect of this preferential recovery on the figures for the relative proportions of different species at unsieved sites.     

ELECTRON SPIN RESONANCE THERMOMETRY APPLIED TO QUARTZITE COBBLES FROM VERGELEGEN SLAVE LODGE,SOMERSET WEST,SOUTH AFRICA

This paper describes the use of electron spin resonance spectroscopy to estimate the degree of heating of quartzite cobbles from hearths on the floor of the archaeological remains of an eighteenth-century Dutch colonial slave lodge. A novel technique based on the comparison of line intensities for the E’and O^-₂ centres in quartz distinguished successfully between cobbles which had been heated to estimated temperatures ranging from 300 °C to 450° C and controls from an adjacent stream bed. This inexpensive and simple technique could be applied to a wide range of archaeological problems involving the thermal history of objects consisting of or containing quartz.     

ELECTRON SPIN RESONANCE STUDY OF PAPER SAMPLES DATING FROM THE FIFTEENTH TO THE EIGHTEENTH CENTURY

Electron paramagnetic resonance spectroscopy is used to detect paramagnetic impurities in differently degraded antique sheets of unprinted paper. Impurities consist primarily of transition metal ions (Fe³⁺, Mn²⁺, Cu²⁺) present in different environments and symmetries. Organic radicals, common in modern, wood pulp paper, are absent in these antique samples made from rags. Fe³⁺ is the largest impurity (from 300 to 700 ppm). Mn²⁺ is also present but its concentration does not exceed 50ppm. Cu²⁺ has been detected in about one-third of the samples. Coupled with nuclear magnetic resonance data, these results describe degradation as an hydrolytic process leading to a net increase of amorphous cellulose and to a decrease of bound water. Copper and rhombic iron appear to act as efficient degradation catalysts, whereas the presence of octahedral iron is almost irrelevant.     

THE SEARCH FOR THE ORIGIN OF BITUMEN EXCAVATED FROM ARCHAEOLOGICAL SITES IN THE NORTHERNMOST ISLAND IN JAPAN BY MEANS OF STATISTICAL ANALYSIS OF FI–MS DATA*

The origin of bitumen excavated from archaeological sites in Hokkaido, the northernmost island in Japan, was sought by means of field‐ionization mass spectrometry (FI–MS) and gas chromatography – mass spectrometry (GC–MS) of the hydrocarbon components. The field‐ionization mass spectra were decomposed by Z‐numbers into several components, where the Z‐number refers to z in the formula C _n H _2n+z . This is equivalent to the deficit number of H atoms, when compared to the corresponding saturated hydrocarbon, which is related to the number of saturated hydrocarbon rings in alkanes. By use of the spectral intensities of the seven alkane components in each sample, multiple discriminant analysis was employed for the data of raw bitumen samples and excavated samples from archaeological sites. Based on this method and the gas chromatogram type, the following bitumen trade in the prehistoric age of Japan was elucidated: bitumen from Niigata, one of the main sources on the main island of Japan, spread to the north in 2000 bc , probably via the coastal zone, and reached a small island near the north end of Hokkaido. Bitumen from Sakhalin reached the central lowland in Hokkaido, but it went no further. Bitumen from Akita, another main source on the main island, spread over northern Honshu much earlier and reached the Oshima peninsula, the southwestern part of Hokkaido. The Akita bitumen scattered into the central lowland after the Niigata and Sakhalin bitumen. This area is believed to be the place where people from the south and the north met in those periods.     

ELECTRON SPIN RESONANCE STUDY OF WHITE MARBLES FROM THARROS (SARDINIA): A REAPPRAISAL OF THE TECHNIQUE,POSSIBILITIES AND LIMITATIONS*

The characterization of various samples of white marble from the archaeological site of Tharros (Sardinia) is the starting point for the reexamination of the capabilities of electron spin resonance (ESR) spectroscopy as a tool for identifying the quarries of origin of ancient marble artefacts. Existing methods and data bases are employed for the assignment of our samples, but also reviewed to see if a more extensive use of the technique is feasible. It turns out that ESR spectroscopy, coupled with other available methods, may readily provide valuable information, often yielding the final answer to the problem of marble provenance. However, it is also clear that much work has still to be done to standardize the data collection and analysis procedures and to expand the available data base.     

PHOSPHORUS ANALYSIS AT ARCHAEOLOGICAL SITES: AN OPTIMIZATION OF THE METHOD AND INTERPRETATION OF THE RESULTS

The application of phosphorus analysis to archaeological contexts can be considerably improved through ultrasonic extraction and the statistical evaluation of results through an analysis of variance. Such tools make the archaeological application of phosphorus analysis faster as well as more economical and coherent. This paper describes the features of these tools and provides a practical case: the Late Neolithic—Early Copper phase of the site ‘Polideportivo’in Martos, southern Spain.     

A PROVENANCE STUDY OF POTTERY FROM ARCHAEOLOGICAL SITES NEAR CANOSA,PUGLIA (ITALY)*

Studies have been carried out to assess the provenance of selected pottery excavated at archaeological sites near Canosa, Puglia (Italy). Sixty-six sherds, ranging in date from the mid-seventh century BC to the beginning of the third century BC, were analysed by atomic absorption spectroscopy and 16 elements were determined. The analysis data were subjected to multivariate classification procedures. Tests showed that the majority of the examined sherds came from ancient local kilns; a probable Ionian origin was established for some other sherds, while the rest were of unknown origin.     

COMPOSITIONAL INHOMOGENEITY OF SEDIMENTS AND ITS POTENTIAL EFFECTS ON DOSE RATE ESTIMATION FOR ELECTRON SPIN RESONANCE DATING OF TOOTH ENAMEL

We present results of particle size and radioactivity analyses of sediment samples collected from five sites with different burial environments. The uranium, thorium and potassium concentrations in the five sample sets are shown to vary with particle size. The potential effects of the observed size-dependent variations on electron spin resonance (ESR) dating of tooth enamel are assessed using two hypothetical models. Our results show that any bias to relatively fine fractions could result in a significant overestimation of the total environmental dose rate, leading to an underestimation of the calculated ESR age.     

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.     

INVESTIGATION OF ELECTRON PARAMAGNETIC RESONANCE PEAKS IN SOME POWDERED GREEK WHITE MARBLES*

Within the context of white marble provenance research, 42 powdered white Greek marbles have been characterized using electron paramagnetic resonance (EPR) spectroscopy. Phase analysis was first carried out to separate calcitic and dolomitic marbles, then EPR spectra of Mnuc were studied. Investigation of other marble EPR spectra, especially around g — 2.00, led us to characterize five different signals. The intensities of Mn²⁺ lines permit the separatum of eight quarries into two groups, allowing a first discrimination, in the g = 2,00 region, only one signal has been found to be useful for provenance research objectives. The results are cheering and should lead to many other similar experiments.