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The aim of this paper is to analyse the role of wheat quality in the formation of wheat prices in the early modern period, adopting eighteenth-century northern Italy as a case study. Wheat prices have been widely used by economic historians to calculate living standards, determine the degree of market integration, and date famines. Rarely, however, have economic historians focused on how wheat prices were determined. By looking at the wheat supply chain, we will try to make more visible the extent to which wheat quality was crucial in determining the value of wheat and, as a consequence, the final price of grain.

This study estimates the cost of living in three cities – Florence, Bologna and Milan – in eighteenth-century northern Italy. Although they do not allow an understanding of the differences between social groups or seasonal consumption patterns, the calculation of living costs and the implied modelling have a twofold aim. First, they allow the calculation of real wages, which are obtained by dividing nominal wages by the cost of a consumption basket; therefore, broadly, they allow the Italian case to be put into great debates of economic history, such as the one on the Little Divergence between northern and southern Europe at the end of the early modern period. In this regard, we will show that the existing calculations used for this purpose have many criticalities, and we will solve them. Second, determining the cost of consumption baskets allows us to observe the role played by urban public institutions in mediating between the market and consumers, with relevant effects on price trends and, therefore, on the purchasing power of the urban population.

In this study, we report the experimental findings of a multi-methodological and comparative investigation of a natural (from the Wah Wah Mountains of Beaver County, Utah) and three synthetic (hydrothermally grown) gem-quality red beryls by means of: gemmological standard testing, laser ablation inductively coupled mass spectroscopy, infrared and Raman spectroscopy, ultraviolet–visible–near infrared absorption spectroscopy, and single-crystal X-ray diffraction. Gemmological, crystallo-chemical, and spectroscopic features of the natural and synthetic stones enabled us to unveil the causes of their color (from red, to purplish-red, or orange-red) and how different and complementary techniques can be efficiently used to discriminate between natural and synthetic materials, based on non-destructive, micro-destructive, and destructive techniques.

Agates from Yozgat province are appreciated on the gem market for their white and purple-blue banded colours. In this study, we present a detailed investigation aimed at the identification of the atomic and structural origin of this peculiar colouration of chalcedony. X-ray diffraction and Raman spectroscopy revealed the presence of fine grains of quartz and moganite with a preferential accumulation of the latter in the blue bands. Near-infrared diffuse absorption spectra show overtones of hydroxyls vibrations at 1425, 1900, and 2250 nm. In the visible, the broad absorption at about 500 nm, as well as its behaviour at low temperatures, is compatible with the optical activity of iron impurities in quartz matrices, such as that observed in amethysts. Peak intensities and shapes are very similar for spectra collected in blue and white bands. Accordingly, trace-element composition from laser ablation inductively coupled mass spectrometry confirmed that the two regions have similar Fe content. The perceived changes in band colours are indeed originated by differences in microstructural arrangement and size of the grains visualised through scanning electron microscopy. White and blue stripes have grains of about 5 µm and 300 nm in size, respectively, resulting in an accentuated scattering component for the white bands. Therefore, the unique purple-blue shades typical of Yozgat agates are a combination of iron-related colour centres and scattering effect.

The book investigates some aspects of the Italian economic development looking at some usually forgotten cases of international success: the small-medium enterprises specialized in “light” productions, such as food, beverages, and apparel. These firms have shown a peculiar ability to adapt, in order to cope with the instabilities of the international markets, modifying both their organization and their business strategies, elaborating an unusual entrepreneurial style, more attentive to the resources, constraints and vulnerabilities of the context.

During the last decades many studies have been carried out to investigate how point defects and aggregates respond and evolve in natural Type Ia diamonds as a result of treatments, and a number of underlying mechanisms have been identified and interpreted. However, the analysis of radiation-induced creation/ionization of defects, as well as their migration and aggregation in secondary defect structures, often requires experimental approaches which can hardly constitute a simple-to-use diagnostic tool for the identification of artificially treated diamonds. Here we disclose a novel simple indicator of artificial exposure of Type Ia diamonds to ionizing radiations and subsequent annealing. This indicator consists in narrow photoluminescence lines in the red region, between 681 and 725 nm, we recently found to result from vacancies trapped by interstitial carbon aggregates and platelets. Our results demonstrate that interstitial structures become sites of vacancy trapping – by thermal migration of radiation-induced vacancies – only when diamond undergoes treatments. We give the rigorous validation of the new spectroscopic probe of artificial treatments analysing photoluminescence and infrared absorption spectra of well-known H1b and H1c centres in a hundred samples. Importantly, the method is based on emission lines which do not require neither high photon-energy excitation nor cryogenic temperatures.

The present research concerns the characterization of samples of corundum (Al2O3), varieties of sapphire, by micro-Raman spectroscopy. Ten samples of natural corundum from Australia, Madagascar, Sri Lanka, Thailand, Tanzania, and Vietnam were studied. After standard gemmological analysis, micro-Raman analysis was also performed in order to identify mineral inclusions within the sapphire samples and to obtain information on the geological genres of the minerals. Several inclusions were evidenced within the sapphires and identified by Raman spectroscopy thanks to a confocal spectrometer, which allowed detection also below the external surface of the gem. Finally, the Raman spectra are discussed taking into account the provenance of the samples and their optical absorption. Copyright © 2008 John Wiley & Sons, Ltd.

Perdite cerealicole con un focus sulla fase dello stoccaggio in epoca moderna

Studio della genesi della tipicità come categoria commerciale in età rinascimentale

Corpus fonti per una storia dell'infiltrazione criminale nell'agro-alimentare italiano