New Insights into the Provenance of the Obsidian Fragments of the Island of Ustica (Palermo,Sicily)

In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA–ICP–MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri‐Tyrrhenian area during the prehistoric age.     

Microstructural and Componential Characterization of the Plating Technology on Chinese Han Dynasty Bronze Fragments

The bronze wares of the Han Dynasty excavated in Chongqing are decorated with plating patterns, maintaining an exquisite lustre right up to modern times after the covering patina is cleared away. In this paper, a plated fragment of the Han Dynasty from the Wushan County Museum was characterized by combining optical microscopy (OM), scanning electron microscopy with X‐ray energy‐dispersive spectrometry (SEM–EDS), X‐ray fluorescence analysis (XRF), X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). The results showed that the bronze fragment was gilded with a ~ 3 μm thick gilded layer and a ~ 20 μm thick silvered layer. The high concentration of Hg and Hg‐rich intermetallic compounds confirmed the existence of mercury gilding/silvering technology, for example, Au₉Hg in the gilded layer and Ag₁₃Hg₇ in the silvered layer. An ordered stripe structure was observed in the gilded surface, corresponding to the formation of rod‐like, intermetallic Au–Hg compounds. Specifically, a high concentration of Au was detected in the silvered layer. The exploration of gilded/silvered bronze casts light on this ancient technology and the benefit of identifying, protecting and reproducing it.     

A Multidisciplinary Approach for the Archaeometric Study of Pozzolanic Aggregate in Roman Mortars: The Case of Villa dei Quintili (Rome,Italy)

This contribution focuses on the study of historical mortars from a Roman archaeological site known as Villa dei Quintili, a monumental villa located in the south‐eastern part of Rome (Italy). The study was carried out on 38 mortar samples, collected from several edifices within the complex. A multi‐analytical approach, including polarized optical microscopy, scanning electron microscopy coupled with energy‐dispersive system and laser ablation inductively coupled plasma mass spectrometry, was used to analyse the pozzolanic material used for the preparation of mortars. Data obtained on both major and trace elements were compared with the compositions of Pozzolana Rossa, Pozzolana Nera and Pozzolanella samples from the Alban Hills volcanic district, collected from a historic quarry nearby, as well as with literature data. The results of such a multidisciplinary approach allowed us to recognize the use of all three pozzolan types for the aggregate fraction of examined mortars from the Villa dei Quintili.     

Twenty Years of Mobilising around AIDS in China: The Main Actors and Influences behind Organisational Growth

AIDS-related work and advocacy is one field that has spurred considerable activity among Chinese NGOs in the past two decades. This article explains processes leading to institutional changes that are necessary for allowing more NGOs to emerge and operate, and shows how international, domestic and local actors and influences have steered developments leading to organisational growth. The article applies new institutionalism theory and highlights differences between formal and informal institutions in explaining change and continuity for NGOs and their relations to state and government in this particular field.