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The fossils of Hamipterus tianshanensis (Wang et al. in Curr Biol 24:1323–1330, 2014) and their eggs have important scientific significance because they can provide unique information about the reproduction, development, and evolution of pterosaurs. The fossils and the rock surrounding them have, however, been weathered, which including powdering and flaking, since they were relocated from Xinjiang to Beijing. The high content of soluble salts is a significant factor in fossil deterioration because the dissolution–recrystallization process can generate tremendous pressure and lead to decreased mechanical strength. This study evaluated the electrokinetic desalination performance for the fossils, and two types of poultices employed including paper pulp from Bioline® and CKS121 (cellulose: kaolin: sand = 1:2:1, w/w). Mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM), ion chromatography (IC), and other methods were applied to evaluate the desalination effect. The surface salt content reduction by applied direct current (DC) was about 70%, and the inner salt content reduction was about 80%. The experimental results suggest that the electrokinetic method is a promising way to desalinate fossils. Nonetheless, cracks appeared in the surrounding rock crack after electrokinetic desalination, which can be explained by the montmorillonite swelling-induced stresses. Pre-consolidation, especially for electro-chemical method may solve the cracking problem for the clay-rich sandstone desalination. [ABSTRACT FROM AUTHOR]

With the emergence and progress of composite tools in the Middle Stone Age, the adhesive became one of the most widely used materials by early human societies. However, the precise composition identification of adhesive in archaeological remains is a real analytical challenge, because the adhesive mainly consists of organic materials that are susceptible to decay during burial process. Of particular interest is to know which animal/plant species were being exploited for glue manufacturing other than for food. The arid climate of the Xiaohe Cemetery, located in Taklamakan Desert, northwestern China, provides favorable conditions for the preservation of organic residues. A bone sculpture-inlaid wooden artifact was collected from the Xiaohe Cemetery, with some semi-transparent yellowish adhesive exposed due to the detachment of an inlaid bone sculpture. In this paper, micro samples of the adhesive were scraped for FTIR (Fourier Transform Infrared Spectroscopy, primary examination) and subsequent proteomic analysis to determine the proteinous component(s) and precise origin(s). The identified tryptic peptides match most closely to known bovine collagen markers, suggesting that this adhesive was an animal glue made from cattle. These results reveal the diverse utilizations of cattle in the Xiaohe Cemetery, which provided not only meat, milk, hides, sinews and dung, but also leftover parts for manufacturing adhesive. This is the earliest evidence of adhesive identified in China up to our knowledge, which sheds light on adhesive development around 3500 years ago. [ABSTRACT FROM AUTHOR]

Abstract: Ancient foodstuffs, including noodles, cakes, and common millet, were excavated from the Subeixi Cemeteries (cal. 500–300 years BC), Turpan District in Xinjiang, China. Starch grain and phytolith analyses were undertaken to identify the plant species involved. These indicate that the noodles and cakes were made from Panicum miliaceum. Ancient food preparation technologies were also investigated by cooking experiments. [ABSTRACT FROM AUTHOR]

The discovery of Hamipterus tianshanensis had important scientific significance because three-dimensional preserved fossils can provide unique information about the reproduction, development, and evolution of pterosaurs. However, the pterosaur fossils exhibited violent weathering, including noticeable cracking and spalling, since the preservation environment changed dramatically after excavation, which severely influenced the preservation of these fossils and the scientific research conducted on them. To determine the weathering mechanism of these fossil bones, the samples were analyzed using X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy and energy dispersive spectrometry (SEM-EDS). The results indicate that calcite is the main mineral in the hollow bones, but it is mixed with a small amount of other minerals, such as quartz, feldspar, and other debris particles. Moreover, the main component of the pterosaur bones is hydroxyapatite, and carbonate has substituted for some of the phosphate (B-type carbonated apatite) in the fossil bones. A small amount of calcite and manganese oxides has precipitated in the vascular canals. The phosphate crystallinity index (PCI) is 4.17. These results indicate that the fossils have undergone severe diagenesis. Apart from these alterations, the fossil bones have high contents of anions and cations such as Cl−, NO3−, SO42−, Na+, and Ca2+, and the total content of soluble salts is 35584.41 µg g−1. Based on these results, it is inferred that the weathering mechanism of the fossil bones is as follows. First, the fragile hollow bones cracked easily because of the enormous thermal stress caused by the dramatic temperature changes in the Gobi Desert and the differences in the thermal expansion coefficients (TEC) of the surrounding rocks, the fossil bones, and the different fillers. Second, a large amount of stress is generated by salt crystallization when the temperature and humidity change, and the pterosaur fossils will be damaged when the crystallization pressure exceeds the tensile strength of the fossils. These results suggest that the preservation of pterosaur fossils requires suitable desalination and consolidation conditions. Moreover, they should be preserved in a constant temperature and humidity environment. [ABSTRACT FROM AUTHOR]

Indo-Pacific glass beads are produced by the drawn technique, which originates from South Asia, and their chemical compositions are unique in South and Southeast Asia. However, a small number of Indo-Pacific beads with Sassanian glass compositions are excavated in Asia and Africa after the 3rd c. CE, and their production sites in South/Southeast Asia or in the Sassanian region remain controversial. In this study, 15 drawn glass beads with various colours from Astana necropolis (ca. the 4th-8th c. CE) in Xinjiang, northwest China were investigated by using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), Scanning Electron Microscope, Raman spectroscopy and visible to near-infrared spectroscopy to characterize the production technology and origins. The results show that most Astana glass beads share similar chemical compositions with the glassware from Veh Ardašīr, a famous Sasanian site. Furthermore, Sasanian glass compositions predominate in Indo-Pacific beads in Xinjiang during the 4th-8th c. CE, while popular glass recipes in contemporary South/Southeast Asia are infrequently found; thus, it is deduced that the drawn method should have been mastered by Sasanian craftsmen. Moreover, the cobalt materials in Sasanian glass were imported from further western regions and changed over time. The popular Sasanian glass across central Eurasia reflects the trade monopoly of Sasanian in West and Central Asia, and the land glass bead trade is distinct from the contemporary maritime trade in the Indian and Pacific Oceans. [ABSTRACT FROM AUTHOR]