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On-site Raman spectroscopy is used to investigate four mosque lamps and a bottle dating back to the 13–14th centuries (Syria and/or Egypt, Mamluk period) from the Department of Islamic Art, Musee du Louvre, Paris. The pigments and the enamelled glass matrix have been identified in order to discuss their technology. A comparison is made with one masterpiece from the 19th century made by Brocard. The results obtained for blue (lapis lazuli or Co-coloured glass), yellow (Naples yellows or zinc/chrome yellow), green (mixture of the aforementioned blue and yellow pigments or lead chromate for restorated foot) red (hematite), white (cassiterite or arsenate) and pink (hematite and cassiterite) pigments are presented. The consistency of the pigments period of use/technology with the datation proposed for each artefact is evaluated. For one lamp, the detection of quartz in some places of the hematite-rich glassy layer supporting the gold is related to the search of a physical bonding with the artefact body. Carbon residues in such enamel are consistent with the use of an organic medium to place the enamel powder before the firing. Copyright © 2012 John Wiley & Sons, Ltd.

The comparison of the low wavenumber of polarized Raman spectra (50–300 cm–1) from Bombyx mori (fresh cocoons fibres, hand-stretched ‘Crins de Florence’ strings from the gland content, dried gland, regenerated silk films) and Nephila madagascarensis silks reveals the high polarisation of fibre modes and the absence of polarisation for dried gland and regenerated silk films. This is consistent with X-ray diffraction measurements. The orientation of the fibroin/spidroin chains is due to the stretching during production, as for advanced synthetic fibres. The bandwidth of the ‘ordered chains’ signature is almost the same for the different fibres. However, the degree of polarisation seems to be higher in the case of spider fibre. The huge bandwidth of low wavenumber components of regenerated films indicates high disorder. Measurements along the fibre point out conformation changes with a periodicity (~20 mm) related to the silkworm head motion during the fabrication of the cocoon. Copyright © 2012 John Wiley & Sons, Ltd.

The assignment of Asian bronzes and brasses is difficult because the copies of ancient pieces have been made a long time ago in different countries. A selection of 30 Japanese and/or Chinese bronzes/brasses are studied on-site in the storage and exhibition rooms of the Cernuschi Museum, in Paris, using portable Raman and X-ray fluorescence spectrometers. Attempts are made to identify specific Raman signatures of the patina to detect similarity in a nondestructive procedure. X-ray fluorescence measurements allow an identification of two brass artefacts and different types of bronze, including lead-rich and mixed lead–tin–zinc-rich compositions. The following phases are identified: CuO, Cu2O, Cu2S, tin oxides, ZnO, Cu3(OH)4SO4, Cu4(OH)6SO4, 3PbOPbSO4 H2O, PbSO4/PbO, Pb(AsO4)3Cl, HgO/HgS. Relics of the mould, retained as concretions at the artefact surface are also identified: TiO2, SiO2, and different soda(−lime) glasses. Patina with very similar colour and habit may have different Raman signatures. This study offers tools to classify the artefacts in a noninvasive way. Copyright © 2011 John Wiley & Sons, Ltd.

About 200 coloured glass beads (red, yellow, green, blue, white, black, pink, plum) excavated on Mapungubwe hill and at K2, archaeological sites in the Limpopo valley South Africa, were studied with Raman scattering. This is also the most southern site in Africa where evidence for glass reworking has been found. The glass matrix of the beads was classified according to its Raman signature into three main subgroups and corroded glass could also be identified. At least seven different chromophores or pigments (lazurite, lead tin yellow type II, Ca/Pb arsenate, chromate, calcium antimonate, Fe–S ‘amber’ and a spinel) were identified. Many of the pigments were manufactured after the 13th century, confirming the presence of modern beads in the archaeological record. This calls for further research to find a way to reconcile the carbon dating of the hill, which currently gives the last occupation date on the hill as 1290 AD with the physical evidence of the modern beads excavated on the hill. The results are discussed in terms of the glass production origin of the beads (Europe, Mediterranean area, India, China). Copyright © 2011 John Wiley & Sons, Ltd.

Six French miniature portraits on ivory and paper dating back to the 18th to 19th centuries have been studied by Raman spectroscopy. The miniatures have been investigated through their protective glass cover using different operating conditions: various laser wavelengths (1064, 785 and 532 nm), spectrometers (fixed and mobile) and objectives (10× to 200×). The results obtained for black (carbon), grey (carbon + chalk), red (lead oxide, vermillion), blue (Prussian or phthalocyanine blue), green (emerald or Paris green) and white (lead white) pigments are presented. The consistency of the period of use of the pigments with the proposed dating for each artwork is evaluated. Attention is paid to the analysis of the ivory substrates (assigned to Asian elephant ivory) and to the protective glass. Copyright c � 2011 John Wiley & Sons, Ltd.

A selection of red-flashed and red-coated medieval potash lime and 19th century soda lime stained glass pieces were studied in the laboratory using different instruments and laser wavelengths, both at lower and higher than the surface plasmon resonance (SPR) of copper. The Raman signatures of the transparent glass matrix and the red glass layers are discussed and compared with those recorded on model glasses containing a dispersion of Cu0 nanoparticles. Evidence is given that the conformation of the silica network in the vicinity of the metal nanoparticles differs from that of the glass matrix. Hematite and carbon traces are evidenced in the Cu0-rich layers, which is consistent with the use of a combination of a reducing atmosphere and redox couples to control the growth of metallic copper particles. Copyright © 2009 John Wiley & Sons, Ltd.

A selection of 23 rare glass objects, mostly enameled, of various provenance and age, from the 5th century BC to the 19th century AD including the Western and Islamic Middle Ages but with a focus on 16th–18th century Venetian and French ‘facon de Venise’ artefacts, have been studied on-site at the Sevres museum or at the laboratory. The Raman signatures of the transparent or opacified glass matrix and of enameled decorations are discussed and compared to those previously recorded on ceramics and stained glasses. The Raman parameters allow discrimination between 2 groups (with some variations) of glass bodies, belonging to mixed Ca–Na and Ca-containing Na-rich silicates, with some exceptions. Most enamels are instead lead-based glasses, but we also found enamels having a composition close to that of the glass body. Most of the pigment signatures are similar to those recorded on ceramic glazes, which proves the link between the two technologies. A particular emphasis was given to the identification of white opacification techniques. Very specific signatures could question the authenticity of some artefacts, and at least in two cases, arguments have been found to identify a fake or embellished artefact. Copyright © 2008 John Wiley & Sons, Ltd.

Red and yellow natural (roasted) pigments have been used for millennia. This paper reports on the Raman characterization of about 50 pigments of the Okhra ‘Matheriautheque’ collection from different origins: violet, red, orange, apricot, yellow ochre, Umbrian and Siena earths from France (Puisaye, Ardennes, Vaucluse), Italy (Siena, Sardinia, Venice, etc.), Germany, Sweden, Cyprus and India (Madras). Comparison is made with ‘Bengara’ Japanese pigments. Goethite is the chromophore of yellow pigments, and haematite (sometimes with magnetite) that of red ochre and earths. Umbrian pigment (‘Terre d'Ombre’) contains additional manganese oxides. Color shades are related to the content of secondary phases: iron oxides (haematite, goethite, magnetite), quartz, gypsum and anhydrite, calcite, dolomite, alums (jarosites), and to the Fe/M substitution in the haematite structure. The set of secondary phases can be used to confirm a provenance signature (Supplementary Material available). Copyright © 2008 John Wiley & Sons, Ltd.