Synthesis, Rietveld refinements and Raman spectroscopic studies of tricationic lacunar apatites Na1−xKxPb4(AsO4)3 (0⩽x⩽1)

Ambrosi

Ngo

et al. 2017

International audienceThree porcelain shards representative of wucai (Famille verte, Famille rose and fencai), enamelled wares from Kangxi, Yongzheng and Qianlong reigns have been studied using fixed instruments (optical microscope, EDS-SEM and Raman microspectrometer) in order to identify the amorphous and crystalline phases in the glaze, body and the different enamels. A comparison is made between the information collected with portable Raman setups excited with 532 and 785 nm lasers and equipped of sophisticated optics. Emphasis is put on the detection of pigments and opacifiers, in particular arsenic-based phases in blue coloured areas, in relation with the use of cobalt ores originated from European or China. The mobile Raman setup excited with green laser and equipped with a high magnification (x200) ultra long working distance microscope objective allows the identification of all the phases, as for the fixed instrument excited with blue 457 nm laser line. Confirmation of the identified phases is made by SEM-EDS. The old technologies are discussed and compared to those used to produce 18 th century French soft paste porcelains and Limoges enamels

Section: Famille Verte Enamelsmentioning

confidence: 99%

Comparative analysis of wucai Chinese porcelains using mobile and fixed Raman microspectrometers

Ambrosi

Ngo

et al. 2017

“…Recently, elemental composition analysis suggested the association of (European) cobalt and arsenic in the blue décor of some Famille rose porcelains [78]. The different wave numbers could indicate different compositions of Pb-Ca solid solution [79]. For vivid blue-coloured enamels, the superimposition of the olivine Co 2 SiO 4 contribution (ca.…”

Section: Raman Signaturesmentioning

confidence: 99%

Non-invasive Raman analyses of Chinese huafalang and related porcelain wares. Searching for evidence for innovative pigment technologies

Zhang

Zhao

2017

104

Eighteen Chinese painted enamelled porcelains and three Chinese enamelled Yixing stonewares dated to the 16 th to 19 th centuries and kept at the Musée national des arts asiatiques-Guimet (MNAAG), have been analysed with a mobile Raman set-up to identify their enamelling technology. Different Grand Feu (leadless or lead-poor colourless and blue enamel) and Petit Feu (lead-rich red (hematite), yellow and green (Pb-Sn/Sb/X pyrochlore) and black enamels) glazes were respectively identified on wares from the wucai group, the Famille verte group, and the huafalang group. Calcium phosphate was detected in a 17 th century vase as a rare opacifier. Cassiterite was identified in the light green glaze of an imperial huafalang bowl dated to the final period of the Kangxi reign (1662-1722), ca. the 1 st quarter of the 18 th century. Lead arsenate was identified in the blue glaze of two artefacts, a huafalang bowl and a painted enamel water dropper, and in the blue enamel of a 19 th century Yixing teapot. Lead arsenate found in some of the blue enamels appears to arise from the arsenic content in Erzgebirge cobalt ores and not due to voluntary addition. This may prove the use of raw materials or enamel powder imported from Europe in developing these opaque colours. The use of lead arsenate as white opacifier is clear for a water dropper bearing the Yongzheng emperor's mark (r. 1723-1735). The technological palette appears different for the artefacts expected to originate from the same period and provenance (imperial workshop) which is consistent with a period of intense innovation, open to technological skill from abroad -i.e. from French/European painted enamel technology -as revealed by ancient French (Jesuits) and Chinese historical reports. Graphical abstract 2

“…The intensity of Si-O stretching tends to be much lower than that of As-O because of the smaller polarizability and the lower number of electrons involved in the bond. Thus, the stretching band of arsenate-based compounds is always very strong and peak between 800 and 830 cm -1 [48,49]. The change in the peak positions might possibly be due to the formation of different solid solutions of lead arsenate where Pb may partially be substituted by K, Na and Ca ions due to the glaze composition [49].…”

Section: Pigmentsmentioning

confidence: 99%

On-site Raman analysis of 17th and 18th century Limoges enamels: Implications on the European cobalt sources and the technological relationship between Limoges and Chinese enamels

Arberet

Kırmızı

2017

International audienceLimoges enamels on metal from the 17th to 18th centuries were analysed by non-invasive Raman microspectrometry with a mobile set-up in storage at the Musée des Arts Décoratifs (Paris) in order to identify the types of glazes and pigments used and to compare them with those found in Chinese cloisonné and falangcai enamels painted on metal and porcelain from the Kangxi and Yongzheng reigns (Qing dynasty). Certain French Jesuit and Chinese historical records report exchanges of technical know-how and artefacts during this period from France to China. Particular attention is paid to the detection of lead arsenate in blue and white enamels as well as in the whitened ones. Lead arsenate appears to be formed in blue enamels due to the high arsenic content of European cobalt ores exploited during the period in question