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Various techniques such as Raman spectroscopy, X-ray diffraction, and thermal expansion measurement have been applied to Sa Huynh (10th century BC–2nd century AD) and Cham (2–15th centuries AD) pottery findings from the excavations at Quang Ngai province (Central Viet Nam). The experimental results highlight the microstructure and technological processing of these potteries. Sa Huynh potteries technology is based on iron-rich clay-based body and feldspar fluxing agents. The firing is made in more or less strong reducing conditions. The Cham potteries were made from high-temperature fired silica-rich bodies covered with thin colourless to black–brown glazes. © 2004 Elsevier SAS. All rights reserved.

EDS, X-ray fluorescence, Raman spectroscopy, thermal expansion‐shrinkage measurement and scanning electron microscopy were applied to determine the elemental components, structural phases and glazing temperatures of the transparent glazes, blue underglaze and overglaze tam thai (including gold-like lustre) decorations from the 15th-century Vietnamese porcelains/stonewares found at the Chu o âu‐My Xa kiln site and in the Cu Lao Cham (Hoi An) cargo. The ancient technology for colouring the glazes is discussed. The various blue tones in the underglazed decor result from cobalt-containing manganese ore, with the intentional addition of iron oxide. The overglaze copper-green and the gold-like lustre were obtained by dispersing copper in lead-based glass. The red colour was made using hematite dispersed in lead-rich flux.

Many European manufactures tried to compete with China and Japanese ware during the 18th century. Due to lack of kaolin they had to test new processes and the microstructure of produced artefacts inherited informations about it : raw materials composition, firing procedure, glaze composition and structure... Usual methods of microstructure analyses are efficient but require sample preparation. On the contrary Raman micro/macro-spectroscopy allows a non-destructive, remote analysis : body and glaze crystalline and amorphous phases can be identified as well as the incorporated nanosized pigments. Glaze Raman spectra allow classification as a function of composition and temperature processing. In this paper attention was focused on the main factories of Paris area : Saint-Cloud (~1700-1766), Chantilly (1725-1800), Mennecy (1737-1773) and Vincennes (1740-1753) / Sevres (1754-1801). We show that technology changes can be recognized from the combination of body and glaze characterization., Au 18ème siècle, de nombreuses manufactures tentèrent de produire de la porcelaine à l'imitation des pièces importées de Chine ou du Japon, mais sans kaolin, explorant différentes solutions techniques pour obtenir l'aspect désiré. La microstructure de ces objets conserve la trace de ces choix techniques : compositions des matières premières de la pâte, procédure de cuisson, composition et structure des émaux... Les méthodes usuelles d'analyse céramique des microstructures identifient en partie ces technologies mais elles sont destructives. Les développements récents de la (micro/macro)spectroscopie Raman permettent de déterminer à distance, sans contact avec la pièce, les phases cristallines et amorphes constituant la pâte, l'émail (ou couverte) y compris les pigments colorant les émaux. L'analyse quantitative du spectre des émaux permet de les classifier selon leur température de mise en œuvre et leur composition. Dans ce travail nous nous intéressons aux productions des principales manufactures : Saint-Cloud (~1700-1766), Chantilly (1725-1800), Mennecy (1737-1773) et Vincennes (1740-1753) / Sèvres (1754-1801). Nous montrons que les différentes productions peuvent être discernées en combinant les analyses Raman des pâtes et des émaux et que pour une même manufacture l'évolution de sa technologie peut être suivie., Colomban Philippe, Robert Isabelle, Roche Cécile, Sagon Gérard, Milande Véronique. Identification des porcelaines «tendres» du 18e siècle par spectroscopie Raman : Saint-Cloud, Chantilly, Mennecy et Vincennes/Sèvres. In: Revue d'Archéométrie, n°28, 2004. pp. 153-167.

Fifteenth century porcelains and celadons are the most interesting ancient Vietnamese ceramics, both from the material and aesthetic points of view. This paper reports on composition, microstructure and technological processing of the Chu Ðâu-My Xa (Hai Duong province) ceramics. Samples come either from the kiln site or from the Cu Lao Cham (Hoi An) shipwreck. Chemical analysis, scanning electron microscopy, EDX analysis, X-ray diffraction, Raman spectroscopy, thermal expansion/shrinkage and open porosity measurements were systematically performed. The results show the Ca (+K)-based glaze, high-temperature-fired bodies, by one- or multi-step firings. Mullite phase (3Al2O3·2SiO2) was formed in large amount indicating the true porcelain quality of the samples under study. The matrices used for overglaze colouring (e.g., the green, red and metallic-lustre) are lead-based low-firing-temperature glasses. Comparison was made for the structural elements and fluxing agents between the 15th century Vietnamese porcelains and the time-corresponding Chinese ones.

Two palettes, characteristic of the production of the Sevres Factory (Manufacture Nationale de Sevres), and representative of ancient glazing techniques, were studied. One was made with coloured glazes/enamels on Bisque (1050 °C) and the other one was composed of Moufle (880 °C) painting colours. Spectra specific to the white (opacifiers), yellow (including Naples yellow), green, pink, ‘brown–red’ and black coatings/paintings were considered. Emphasis was placed on the different Raman peaks arising from coloured coatings specific to ancient artefacts: greens obtained with dissolved Cu ions or from chromium pigments (Victoria green garnets), Naples yellows (Pb2Sb2O7 pyrochlore), green and black spinels and pink sphene. Attention was paid to the effect of pigment grain size on the Raman spectrum. To illustrate the capability of the method, we analysed some old artefacts from the eighteenth and nineteenth centuries. Copyright © 2001 John Wiley & Sons, Ltd.

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Selected ancient Vietnamese (proto)porcelains and celadons (13–16th centuries) from the Ha Lan (Nam Ð inh), Chu Ðâu (Nam Sach, Hai Duong) and Hop Le (Binh Giang, Hai Duong) ceramic kilns were studied by chemical analysis, macro- and micro-Raman spectroscopy, thermal expansion and differential thermal analysis. Raman spectra of quartz, cristobalite, rutile, mullite, anatase, iron oxide, amphibole and glassy phases were analysed and their evolutions are used to discuss the ancient ceramic technology (raw materials used, firing procedures of the glaze and body, etc.). Structural composition data taken from thermal expansion measurements and Raman spectroscopy are in good agreement. Particular attention is given to the analysis of glaze for the feasible discrimination between original artefacts and modern copies. On the basis of experimental results, the samples made at Chu Ð au can be considered as true porcelains, whereas those made at Hop Le and Ha Lan had evolutions towards porcelain and high-temperature-fired fine faience, respectively. Copyright © 2000 John Wiley & Sons, Ltd.

Reference (natural and synthetic) indigo samples were analysed by Raman spectrometry and only indigotin was detected. ‘Jeans’ refers to a specific garment with respect to both the dye, indigo, and the garment cut; from reference spectra of blue-dyed fibres and threads from garments, it is straightforward to observe by Raman microspectrometry the spectra of dyes fixed on threads without chemical pretreatment. On these supports, the spectrum of indigotin shows extra bands assigned to vibrational modes of Bu symmetry, indicating a loss of the centrosymmetry of the molecule and an alteration of its planarity due to the dyeing process. © 1997 by John Wiley & Sons, Ltd.

The carbonaceous Murchison chondrite is one of the most studied meteorites. It is considered to be an astrobiology standard for detection of extraterrestrial organic matter. Considerable work has been done to resolve the elemental composition of this meteorite. Raman spectroscopy is a very suitable technique for non-destructive rapid in situ analyses to establish the spatial distribution of carbonaceous matter. This report demonstrates that Raman cartography at a resolution of 1 microm2 can be performed. Two-dimensional distribution of graphitised carbon, amorphous carbonaceous matter and minerals were obtained on 100 microm2 maps. Maps of the surface of native stones and of a powdered sample are compared. Graphitic and amorphous carbonaceous domains are found to be highly overlapping in all tested areas at the surface of the meteorite and in its interior as well. Pyroxene, olivine and iron oxide grains are embedded into this mixed carbonaceous material. The results show that every mineral grain with a size of less than a few microm2 is encased in a thin carbonaceous matrix, which accounts for only 2.5 wt.%. This interstitial matter sticks together isolated mineral crystallites or concretions, including only very few individualized graphitised grains. Grinding separates the mineral particles but most of them retain their carbonaceous coating. This Raman study complements recent findings deduced from other spatial analyses performed by microprobe laser-desorption laser-ionisation mass spectrometry (microL2MS), transmission electron microscopy (TEM) and scanning transmission X-ray microscopy (STXM).

International audience; The prehistoric site of Vinča, on the right bank of the River Danube, the territory of the City of Belgrade, first excavated by Dr Miloje Vasić (1931-1934) provides Neolithic pottery dating back to 5200 – 4200 B.C. Shards excavated in 1998 (Serbian Academy of Sciences and Arts) have a yellow coating on the external (convex) and red deposit on the internal (concave) side. Raman, IR and X-ray identification prove that yellow-to-red decor deposited on the external faces of pottery is made of ochre, a mixture of hematite, quartz and phyllosilicates. Red deposit, found on some internal surfaces of a pottery, consists of cinnabar (HgS) with some quartz and phyllosilicates. This indicates that cinnabar was not used for decor but for some other purposes, preparations made in ceramic utensils. A comparison is made with the mercury ore from a Suplja Stena mine located ~ 20 km from the Vinča village.

Raman (micro)spectrometry is used as a technique for the understanding and identification of the fabrication technology of ancient faience and glazed terra cotta from Dougga, north-west of Tunisia. Studied samples are assigned to zirides (XI-XIIth), almohades (XIII-XVth), hafsides and ottomane (XVII-XVIIth) periodes. Cassitérite (SnO2) white, (Pb2Sb,O7) Naples yellow, black and (Fe/Mn ?) brown spinels, haematite (Fe2O3) black and unassigned blue pigment have been characterized. Green colour results from glaze doping (by Cu ?), except for recent samples where woUastonite phase, easely colored in green by chrome, is found. A cassiterite-free overglaze is often present. Cassitérite amounts appear too low in ancient samples to really opacify the enamel., L'analyse par (micro)spectroscopie Raman est utilisée pour comprendre et identifier les technologies employées pour l'élaboration de faïences/terres cuites émaillées provenant de Dougga (Nord-ouest de la Tunisie). La chronologie proposée se répartit sur les périodes : ziride, almohade, hafside et ottomane : XI-XIIème siècles, XIII-XVème siècles et XVII-XVIIIème siècles. Le blanc de cassitérite (Fe 2O3), le jaune de Naples (Pb2Sb2O7), des spinels (Fe/Mn ?) pour les noirs et bruns, l'hématite (Fe2O3) pour un noir, ainsi que d'autres phases pour le bleu, sont clairement observés. Le vert résulte d'une coloration dans la masse de l'émail (sans doute du cuivre) sauf pour certains échantillons tardifs (XVII-XVIII th) où la présence de wollastonite rend possible une coloration par le chrome. Un émail de surface exempt de cassitérite est souvent observé. La cassitérite semble avoir été utilisée dans les productions du haut Moyen Age en quantité trop faible pour être un opacifiant efficace., Colomban Philippe, Sagon Gérard, Louhichi Adnan, Binous Housam, Ayed Naceur. Identification par microscopie Raman des tessons et pigments de glaçures de céramiques de L'Ifriqiya (Dougga, XI-XVIIIèmes siècles). In: Revue d'Archéométrie, n°25, 2001. pp. 101-112.

The Raman spectra of 10 isotopic species of polycrystalline NMA were recorded at 35 K between 6 and 200 cm−1. Below 110 cm−1 at least 8 transitions are observed which are mainly due to external modes. Bands located between 110 and 170 cm−1 show unexpected isotopic effects and are interpreted taking into account IR and NIS spectra. A new internal torsional mode around the bond is proposed. The corresponding potential function involves two minima (Δω = ± 10°) separated by a weak barrier (∼600 cal/mole) indicating a nonplanar molecular skeleton.

Les interactions eau-amide-sel sont etudiees, par spectrometrie de vibration, en solution quaternaire dans deux solvants organiques (CH3 CN et THF) et en melange ternaire. Les aides utilises sont le N,N-dimethylacetamide et le N-methyl-acetamide; les sels des perchlorates, des halogenures de tetra-butylammonium et le bromure de lithium. Nos resultats etablissent la fixation des anions sur les hydrogenes de l’eau et sur le groupement NH dans le cas du NMA et la fixation des cations sur le groupement carbonyle des amides meme en presence d'une grande quantite d’eau. Des doubles interactions [math] ont ete mises en evidence. Le role des anions dans la formation de ces especes est discute. Nos analyses montrent que les interactions observees avec un site du groupement peptidique le perturbent dans son ensemble. Une comparaison est proposee entre nos resultats et les phenomenes de transition de structure de polypeptides en presence d’eau et de sels.