Understanding the blue color in antique mosaic mirrored glass from the Temple of the Emerald Buddha, Thailand

Abstract

Two samples of the blue glass produced in the middle 19th century from the Temple of the Emerald Buddha in Bangkok, Thailand, were studied in order to understand the origin of its blue color. The oxide components and trace elements are quantitatively determined by scanning electron microscopy coupled with energy‐dispersive and wavelength‐dispersive spectrometry and laser ablation inductively coupled plasma mass spectroscopy techniques. The results identify the glass type as soda‐lime‐silica glass with high lead content. The 3d transition elements detected include iron, manganese, cobalt, and copper. Combined analyses of X‐ray absorption near edge structures and optical absorbance lead to a conclusion that the antique glass is primarily colored in blue by the divalent cobalt with additional yellow coloration as a result of the trivalent iron. The tetrahedral coordination geometry of these two species was deduced from the XANES pre‐edge intensity and the optical absorption bands of their d‐d transitions. The redox ratios of Fe2+/Fe3+, Mn2+/Mn3+, and Cu1+/Cu2+ in the original blue glass and the reference glasses were determined by the K‐edge XANES analysis. The blue color of the antique glass can be reproduced in a laboratory glass on the basis of composition and melting conditions. Copyright © 2015 John Wiley & Sons, Ltd.

SUT-NANOTEC-SLRI beamline for X-ray absorption spectroscopy

“…The data were collected in the transmission mode. The fine structures are clearly observed in all samples and consistent with those previously reported (Du et al, 2015;Yalovega et al, 2016;Klysubun et al, 2015;Gaur et al, 2009). The insert of Fig.…”

Synchrotron XANES and ED‐XRF analyses of fine‐paste ware from 13th to 14th century maritime Southeast Asia

“…The XRF data were analyzed by using statistical approaches to classify samples in to groups based on their compositions . In addition to commonly used XRF, X‐ray absorption spectroscopy (XAS) is a powerful technique for archaeometry studies . X‐ray absorption spectroscopy is divided into to two regions: (1) the low energy region, which covers photon energy up to about 60 eV above the absorption edge, called the X‐ray absorption near‐edge structure (XANES) and (2) the higher energy region from 60 eV up to ~1000 eV above the absorption edge, called the extended X‐ray absorption fine structure (EXAFS).…”

“…[5][6][7] In addition to commonly used XRF, X-ray absorption spectroscopy (XAS) is a powerful technique for archaeometry studies. [3,4,[8][9][10] X-ray absorption spectroscopy is divided into to two regions: (1) the low energy region, which covers photon energy up to about 60 eV above the absorption edge, called the X-ray absorption near-edge structure (XANES) and (2) the higher energy region from 60 eV up to~1000 eV above the absorption edge, called the extended Xray absorption fine structure (EXAFS). Whereas the EXAFS measurement allows the identification of the nearest neighboring atoms to the absorbing atom to determine the coordination environment for the metal of interest, the XANES measurement can be used to determine the chemical species and oxidation states of the absorbing atoms.…”

The Colors of the Circus Mosaic from Barcino (Roman Barcelona): Characterization, Provenance, and Technology Issues

“…Therefore, copper would be heterogeneously dissolved within the glass matrix or perhaps in the form of sub-microcrystals (not detected by SR tts-µXRD). A concentration of 1 wt% CuO in soda-lime glasses, in the form of a combination of Cu 1+ and Cu 2+ , has been found experimentally to produce a turquoise color [81]. The deep blue color of tesserae, such as tessera #8, is surely induced by the presence of very low amounts of cobalt.…”