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Faience is a kind of ancient ceramic product which was widely found in many areas. Chinese faience appeared in the Western Zhou Dynasty (1046-771BCE), about three thousand years later than western Asia. The sudden and late emergence of Chinese faience implies that its production technology may be influenced by the West. However, little information is known about how the faience productions spread from the West to central China. The Xinjiang Uygur Autonomous Region, located in the northwestern part of China, is one of the most important areas of cultural exchanges between the East and the West since ancient times. The study of faience unearthed in Xinjiang is of great significance to explore the early trade and cultural exchanges between central China and the West. In this paper, Synchrotron Radiation Micro-CT (SR-μCT) and Energy dispersive X-ray fluorescence spectroscopy (EDXRF) have been applied to obtain the information of microstructure and chemical composition of faience beads excavated from Ya’er cemetery (1050-300BCE) in Hami Basin, The Xinjiang Uygur Autonomous Region, China. These faience beads are the earliest faience artifacts in China up to our knowledge and this is the first time to analyze the excavated faience in Xinjiang scientifically. Based on the microstructure of faience beads in CT slices, it is found that two glazing methods, direct application and efflorescence, were used in faience production. Additionally, a cylindrical core made of organic material sustained the faience bead during shaping and firing. According to EDXRF analysis, various glaze recipes have been used to produce these faience beads, possibly indicating different provenance. The characteristics of higher Na 2 O/K 2 O ratio of faience glaze showed that these faience beads might come from the West. Thus, it is suggested that there was a faience road from Western Asia through Xinjiang to central China about three thousand years ago. [ABSTRACT FROM AUTHOR]

Changsha Kiln, located at Changsha in Hunan Province, south of China, is famous for exported and coloured porcelain during the Tang Dynasty (A.D. 7th-10th century) period. Although the opinion that copper-red porcelain originates from Changsha Kiln is widely accepted in academic circles, chemical characters of glaze and colour mechanism of its copper-red porcelain have not been fully investigated and studied. Therefore, a shard of opaque glaze porcelain with red pigments which excavated at Changsha Kiln (A.D. 7th-10th century) was analyzed by Energy dispersive X-ray fluorescence (EDXRF), Synchrotron X-ray absorption near-edge spectroscopy (XANES), micro X-ray diffraction (μ-XRD), microscopy and scanning electron microscopy (SEM) methods. Combining with XANES and μ-XRD results, it indicates that metal copper is the major colouring-generation element status of the red hue. On the other hand, for the first time the study demonstrates that glaze of the sample from Changsha kiln is a typical phase separated-crystalline glaze with large particles surrounding acicular crystals which lead the opaque appearances. Because the sample from Changsha Kiln is Chinese ancient early stage copper-red porcelain relic, it will help to understand the origin of copper-red porcelain in China and enrich the knowledge of Chinese ancient ceramic culture. [ABSTRACT FROM AUTHOR]

In recent years, the application of Bi3+ ions doped luminescent materials in the field of optoelectronics has attracted wide attention. In this paper, CaLaGaO 4 :xBi3+(x = 0.005, 0.0075, 0.01, 0.0125, 0.015, 0.02, 0.025mol) blue phosphors were synthesized by high temperature solid phase method. The theoretical and experimental bandgap values after Bi3+ ions doping is reduced, indicate that electrons can be transferred from valence band to conduction band better after Bi3+ ions doping, which increases the carrier concentration and improves the luminous efficiency. In addition, due to the doping of Li+ ions under 365 nm excitation, the emission intensity is increased by 2.5 times, shows high brightness blue light, with excellent thermal stability (423K/303K = 83 %), quantum efficiency is 56 %, and CaLaGaO 4 :0.01Bi3+, 0.008Li+ phosphor was mixed with (Ba,Sr) 2 SiO 4 :Eu2+ commercial green phosphor and (Ca,Sr)AlSiN 3 :Eu2+ red phosphor in a certain proportion. The WLED combined with 365 nm chip has a high color rendering index Ra = 90.2. Relevant color temperature CCT = 5502K. [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]

Honglvcai (also named red and green porcelain) was prosperous in Jin Dynasty (1115–1234 AD) and had played a pivotal role in ancient ceramic development history in China, connecting with former glazed pottery Tang Sancai and later polychrome porcelain like Wucai and Doucai, but little scientific analysis has been reported up until the present day. In this research, one precious sherd unearthed from Linshui (one major site of Cizhou kiln system) in Hebei province was adopted as specimen for compositional and micro-structural analysis. Optical microscope (OM), X-ray fluorescence spectrometry (XRF) and energy dispersive spectrometry (EDS) in association with scanning electron microscope (SEM) were employed for investigation of the multi-colour decors and black outline. The extensive data reveal that although high lead content has been detected by surface analysis and the iron-rich pigment particles do locate in the middle of the whole vitrified region, the black outline in fact belongs to high temperature fired under-glaze painted decoration, rather than the deceptive low temperature fired lead based over-glaze decor or the generally believed ‘sandwich’ (glazed twice) structure. Furthermore, a corresponding criterion then has been established for differentiation among three main decorating methods, especially for the puzzling ‘sandwich’ effect scenario. Moreover, once this ongoing vexed debate over the nature of the black decoration in Cizhou kiln system has been clarified, it is then reasonable to deduce that, from idealistic and technical point of view, there is no difference between producing prototype like this sherd and real Doucai in Ming dynasty (1365–1644 AD) except for the types of under-glaze pigment. Overall, all these results together firstly provide realising scientific proofs for the origin of Doucai. [ABSTRACT FROM AUTHOR]