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Hesham M. Abdel-Rahman 《Journal of regional science》1990,30(3):359-374
In this paper, I investigate some of the causes of city formation in spatial economies. A model is proposed in which an intermediate differentiated input shared by more than one industry is the cause of the formation of diversified cities. The desire of both the traded-good and the local-good industries to employ a variety of inputs from the intermediate industry provides the reason for the agglomeration of the three industries. In addition, the paper contains a comparative-statics analysis of the model in an open and a closed-city framework. It is demonstrated that the larger the city, the more variety of intermediate inputs the city can provide and the more specialized it is in the production of the traded-good. Moreover, the model suggests that different industrial structures will result in different city Sizes. 相似文献
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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
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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
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