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This paper analyzes and identifies the binders used in the jewel settings of the Baodian and Diexie belts excavated from the tomb of Murongzhi in Wuwei, Gansu, China. Fourier transform infrared spectroscopy (FTIR) indicated the presence of protein in the binder samples. The result of gas chromatography–mass spectrometry (GC‐MS) shows that samples from both contained hydroxyproline, a characteristic amino acid for animal glue. Principal component analysis was performed on one of the samples, and it was concluded that the binder was a mixture of hide glue and egg glue. Further analysis using scanning electron microscopy with energy‐dispersive X‐ray (SEM‐EDX) and laser Raman spectroscopy (Raman) found that a red particulate matter visually identified in the binder was cinnabar, which was apparently added to binder in order to modify the color of the jewels. This study provides a basis for the conservation and restoration of future finds of elite jewelry. It also shows how imperial jewelry was made during the Tang Dynasty. Finally, the analysis of these heraldic belts provides a key insight the life and role of an exiled prince in the Tang court. [ABSTRACT FROM AUTHOR]

The reliquary bust of Saint Lambert, hosted in the Treasure of the Liège Cathedral, was produced in the early 15th century. This exceptional goldsmithery piece is covered with gold‐coated silver, and decorated by approximately 400 stones, analysed by Raman and pXRF techniques to determine their mineralogical and chemical composition. The results confirm the identification of one hundred pearls, twenty‐six rock crystals, ten amethysts, two diamonds, and numerous glass beads with a green, blue, colourless, turquoise, orange or red colour. The glass beads show a soda‐lime composition, confirming that they are contemporary of the bust and imported from Venice, as reported by historical sources. Orange beads show a lead composition and the red stone a triplet with quartz, indicating that they were added to the bust later. The cutting of gems and beads shows also a significant evolution. The metal contains approximately 60% of Au and 40% of Ag. The origin of gemstones was difficult to establish, due to the absence of characteristic trace elements, but the chemical elements used for the manufacture and colouring of the beads were determined. This study confirms the trade of stones between Liège and Venice during medieval times. [ABSTRACT FROM AUTHOR]

A group of 18 cameos dated from the 16th to 19th centuries (bearing motifs of Roman emperors and female members of their families) from the Constantine Schmidt-Ciążyński collection was investigated with gemmological analyses, supported by non-destructive mineralogical methods such as X-ray diffraction (XRD) and micro-Raman spectroscopy (RS) to ascertain the material used. Although there is no scientific method to date the specimens precisely, the mineralogical data supported by archaeological analyses enabled the estimation of the possible timing of the manufacture of the gems. As a result, the cameos were divided into four basic chronological groups: (1) Renaissance, (2) Baroque, (3) uncertain and (4) Classical and Neoclassical. [ABSTRACT FROM AUTHOR]

In this work, we studied coloured and colourless glass used as gems in Visigothic buckles possibly originating from the necropolises of Torredonjimeno, Duraton or Castilltierra in Spain. Scanning electron microscopy ( SEM) with energy-dispersive analysis ( EDS) and observations made with an optical microscope in reflected and transmission mode were performed in order to establish the composition, origin of the colour and decay process of these glass pieces. The chemical analysis of ancient glass can provide relevant information regarding the manufacturing approach used during a specific period. The results revealed the presence of various transition metal elements used as chromophore elements, as well as some metallic backing foils used to improve the colour of pieces of almost colourless glass. [ABSTRACT FROM AUTHOR]