QUANTITATIVE ANALYSIS OF COPPER-TIN BRONZES BY MEANS OF GLOW DISCHARGE OPTICAL EMISSION SPECTROMETRY

Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed.     

AGGREGATION ERROR EFFECTS ON THE DISCRETE-SPACE p-MEDIAN MODEL: THE CASE OF EDMONTON, CANADA

The spatial analysis literature recognizes three sources of aggregation error, termed Source A, Source B, and Source C, which affect models relying on distance measurements between populations and facilities. We consider these effects with respect to aggregating from census enumeration areas to census tracts, on a popular location model. We identify a further source of aggregation error, which we dub Source D error, arising from the representation of facility sites by discrete points. Source D effects are of the same magnitude as Source A and B combined, much greater than Source C effects. Source D error is further significant, because, unlike Source A and B error, it can be eliminated only by disaggregating .
La littérature sur Vanalyse spatiale reconnaît trois sources d'erreur d'agrégation appelées erreurs de source A, B, et C. Ces erreurs influencent les modèles qui reposent sur des mesures de distance entre des populations et des installations. On considère les effets d'agrégation des secteurs de dénombrement en secteurs de recensement sur un modèle de localisation courant. On identifie une quatrième source d'erreur d'agrégation appelée erreur de source D. Cette erreur découle de la représentation des sites des installations par des points discrets. Ses effets sont du même ordre de grandeur que ceux des sources A et B combinées et beaucoup plus grands que les effets de source G. L'erreur de source D est d'autant plus significative à cause du fait que, contrairement aux erreurs de source A et B, elle ne peut être éliminée que par la désagrégation .     

Beyond Gender Roles? Conceptualizing the Social and Economic Lives of Rural Peoples in Sub-Saharan Africa

The repeated failure to design and appropriately target policies and interventions which address the needs of rural peoples in Africa suggests that something may be wrong with our understanding of the way that these peoples live their lives. Perspectives which focus on intra-household processes, and on gender issues in particular, represent useful advances in the way that the social and economic lives of Africa's rural peoples are conceptualized. However, this article questions the value of adopting development planning, policy and project approaches based on the rigid identification of `gender roles'. By reference to field research undertaken in northern Ghana, the paper aims to demonstrate that other social constructs, such as marital status and seniority, may be as important as gender in determining the roles and status of individuals in African rural societies. The article concludes by highlighting a number of practical implications of this finding in terms of the structuring of development-oriented research and the targeting of policy and interventions.     

ANOMALOUS CARBON-13 VALUES FOR FIBRE TEMPER IN CERAMICS*

Ceramic vessels from Later Stone Age sites in the Seacow river valley, South Africa, were heavily tempered with C4 grasses. However, most δ¹³C values of the temper fall between the known δ¹³C ranges for C4 and C3 grasses. Among possible C3 additives that could skew the signal, ground bone, animal dung, alpine grass, Karoo scrub ash, and humic acid contamination are eliminated. The sherd surfaces yield fatty chars with C3-like values. Although these are not enough to account for all the skewing, they represent only the final cooking event. They were preceded by many such events in which fat was absorbed into the C4 grass then charred to soot by later periods in the fire. Thus organic carbon with the isotope composition of the fat built up while the vessel remained in use.     

SOIL PHOSPHATE ANALYSIS: A NEW TECHNIQUE FOR MEASUREMENT IN THE FIELD USING A TEST STRIP*

A new method for soil phosphate analysis has been developed for field measurement which will increase the applicability of phosphate mapping in archaeological prospection.     

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.     

LIME PLASTER AS AN ADHESIVE FOR HAFTING EIGHTEENTH-DYNASTY FLINT SICKLES FROM TELL EL DAB'A,EASTERN NILE DELTA (EGYPT)*

A combination of analytical techniques, including thin-section observations, scanning electron microscopy, X-ray diffraction and X-ray fluorescence analysis, was applied to study the nature and origin of an adhesive used for mounting flint sickle blades to a wooden handle, recovered from early Eighteenth Dynasty culture layers of the multi-layer settlement at Tell el Dab'a, Lower Eygpt. The results obtained from these investigations led to the conclusion that the adhesive is a pure lime plaster, thus providing the oldest evidence for the use of this material as a binding agent so far known in ancient Egypt.     

X-RAY FLUORESCENCE AND DENSITY MEASUREMENTS ON SURFACE-TREATED ROMAN SILVER COINS*

Some 630 Roman silver coins excavated at Augusta Raurica (Switzerland) have been analysed by non-destructive X-ray fluorescence and X-ray diffraction. Furthermore, the density and the weight have been determined. The measured average density of plated and massive depletion-silvered coins is lower than the density calculated from the chemical composition, whereas massive coins display equal values for both of the densities. Based on experimental X-ray investigations of modern silver (tempering, acid treatment, production of corrosion layers), the nature of corrosion products on silver, their impact on surface analysis, and aspects of wearing-off by circulation are briefly discussed.     

Food Security in India: Measures,Norms and Issues

Although assessments by conventional macro measures show considerable improvement in food security in India, the levels of cereal consumption and calorie intake of even the general population are still below the normative threshold limits. This article brings out the dynamics of changes in institutional and production conditions and their implications for consumption patterns and food security at the micro level. The article uses empirical evidence to raise a number of issues, and calls for emphasis on investment in human capital by way of improvements in food and calorie intake for efficiency and economic growth.     

SPATIAL DEPENDENCY OF SEGREGATION INDICES

A few researchers have mentioned the scale sensitivity of segregation index, D. In this paper, I discuss analytically and empirically why using large enumeration areal units usually results in low segregation measures, and using small areal units produces relatively high segregation measures. The discussion is also applicable to the multi-group variant of D. A major finding is that if people of the same ethnic groups are positively spatially auto-correlated, increasing the size of areal units of analysis may not lower D initially, because only people of the same group are added. But enlarging the areal units subsequently may include population of other ethnic groups, and therefore could lower D. However, if the boundaries of the larger enumeration units are drawn to include only population of the same group, then D will not change significantly. Both the spatial autocorrelation of ethnic group population and zonal pattern are critical factors in determining the scale sensitivity of D.