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81.
Archaeometric analysis of ceramic production in Tiwanaku state (c.500–1000 ce): An exploratory study
J. P. Ogalde A. Korpisaari C. Riera‐Soto B. Arriaza C. Paipa P. Leyton M. Campos‐Vallette N. Lara J. Chacama 《Archaeometry》2021,63(1):53-67
The chemical and mineralogical characterization of seven ceramic fragments produced within Tiwanaku state (c.500–1000 ce ) is reported. The instrumental techniques used included X‐ray elemental and mineralogical chemical analysis, Raman spectroscopy, and scanning and light microscopy. The results indicate there are several clay types, although they show similarities, such as the use of a plant‐based temper. The red colour of the decoration is hematite, and manganese oxides such as jacobsite are present in the black. The white colour is a mixture of gypsum and clay, and the orange is a mixture of hematite and clay. The use of colours, the quality of the clays and the temperatures reached during pottery firing point to expertise in ceramic production and to complex decision‐making processes. The multi‐elemental archaeometric approach documented here could become an important tool to shed a light on ancient ceramic technology and the internal variance of Tiwanaku pottery. 相似文献
82.
In order to carry out strontium (Sr) isotope analysis, glass artefacts from South Asia were sampled with portable laser ablation (pLA), a relatively novel sampling technique that leaves damage invisible to the naked eye. Subsequently, thermal ionization mass spectrometry (TIMS) was used to obtain Sr isotope ratios after sample dissolution and separation. In this study, the goal was twofold: to determine whether the measurements of Sr isotope ratios were impacted by using a portable laser as a sample tool; and to assess the pertinence of using Sr isotope ratios to provenance Indian glass. Despite a deterioration in the precision of the measurement of the Sr isotope ratios for artefacts sampled with pLA compared with the traditional sampling method, the Sr isotope ratios of certain Indian glass are so different that this does not affect their separation but a comparison of data sets obtained using standard methods and pLA might be challenging. 相似文献
83.
F. Albarde J. Blichert‐Toft F. de Callataÿ G. Davis P. Debernardi L. Gentelli H. Gitler F. Kemmers S. Klein C. Malod‐Dognin J. Milot P. Tlouk M. Vaxevanopoulos K. Westner 《Archaeometry》2021,63(1):142-155
The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican‐era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb‐poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce , the Romans brought together the efficient, millennium‐old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks. 相似文献
84.
Elizabeth C. Delmelle 《Geographical analysis》2021,53(1):148-156
The fiftieth anniversary of Geographical Analysis occurs for many quantitative human geographers at an exciting era of new and exciting sources of data and computational advancements. However, it also represents a crossroads where excitement to quickly capitalize upon these new data sources and methods risks reverting the discipline back to its abstraction‐rich and overly generalized roots, erasing much progress made in the pages of this journal that advocated for the recognition of individual differences and need for alternative and even qualitative data sources. In this commentary, I reflect on what we can do over the next 50 years to ensure that the journal is producing research that is socially impactful and better able to explain the messiness of social reality. 相似文献
85.
Discriminant analyses of distances and angles obtained from 25 coins struck by P. Crepusius in 82 BC permitted the correct chronology for five groups of closely-related dies to be obtained by the method of Carter and Frurip. Twenty distances and 15 angles were measured on 10 x projections of the coins which represented five groups of dies separated in time from each other. The use of all or many variables gave poorer results than the use of five to ten variables having a high ‘figure of merit’, defined as the maximum range of mean values for a given variable in the five groups of dies divided by the mean standard deviation of the variable in the five groups. It is recommended that chronologies of ancient coins be determined from Mahalanobis distances by using only variables of relatively high figure of merit. 相似文献
86.
The raw material used largely determines the type and quality of porcelain produced. Twenty-three raw materials used for making Ding, Xing, Gongxian and Dehua porcelain bodies were studied using principal component analysis. Results show that for Dehua wares, only one raw material was used. For Ding wares, although there were many possible raw materials, the use of one alone is unlikely. Lingshan clay was the main raw material but it has to be mixed with other raw materials: Pinjiawa clay, quartz, feldspar and dolomite. The Xing pieces can be divided into three groups and Gongxian wares into two groups, which are discussed in detail. 相似文献
87.
The conventional model of the relationship between welfare incentives and poverty rates holds that welfare payments produce an income-enhancement effect that removes families from poverty until some threshold. Beyond this point increased payments engender a work-disincentive effect resulting in increased rates of poverty. We challenge the model's assumption that poverty levels are a simple and spatially invariant response to welfare incentives, contending instead that local employment conditions may substantially alter the relation. Our reformulation of the conventional modeling approach is based on the expansion method. Specifically, we extend the model to include the effects of local labor-market conditions on the response of poverty levels to welfare incentives. In contesting the invariance assumption, the expansion method allows us to determine where and in what contexts welfare is “work discouraging.” The empirical analysis, which is undertaken at the county level, indicates that welfare payments vary in their influence on poverty rates across different employment contexts. A national map portraying this parameter instability demonstrates that female-family poverty rates are most responsive to welfare assistance in the rural South and least responsive in the metropolitan Northeast. Finally, we examine two sharply contrasting locales to illustrate how poverty is governed by specific employment and welfare characteristics. 相似文献
88.
Nabaitu J Bachengana C Seeley J 《Africa : journal of the International Institute of African Languages and Cultures》1994,64(2):243-251
"The aim of this study was to examine people's beliefs about the causes of marital instability in a rural population cohort in south-west Uganda. Results from a baseline survey of HIV-1 infection in the cohort of over 4,000 adults (over 12 years old) showed a twofold increase in risk of infection in divorced or separated persons when compared with those who are married. A purposive sample of 134 respondents (seventy-two males, sixty-two females) selected to represent different ages, religions and marital status were asked in semi-structured interviews to comment on the reasons for continuing marital instability in their community. The most common reasons suggested for marital instability were sexual dissatisfaction, infertility, alcoholism and mobility....HIV infection was not mentioned as a direct cause of separation, but a small independent study revealed that seven out of ten couples separated on learning of a positive HIV test result of one or both partners. Marital instability is not uncommon in this population; there is evidence that HIV infection is making the situation worse." (SUMMARY IN FRE) 相似文献
89.
90.
D. E. NELSON G. CHALOUPKA C. CHIPPINDALE M. S. ALDERSON J. R. SOUTHON 《Archaeometry》1995,37(1):151-156
Accelerator mass spectrometry radiocarbon ages have been taken for a test suite of small samples of material removed from some of the ‘beeswax’art figures found in rock shelters in northern Australia. The results indicate that we can reliably date this unique form of rock art with no noticeable damage. We had not expected to find figures of any great antiquity, and so we were surprised to find that the ages obtained spanned the time period from the recent past to about 4000 BP. 相似文献