À l’occasion du colloque du GMPCA organisé à Rennes en 2017 (quarantième anniversaire de la première édition) ont eu lieu une série de conférences invitées destinées à ouvrir une réflexion historiographique sur l’archéométrie. Cet article présente cette initiative et introduit les contributions issues de ces conférences qui sont rassemblées dans ce numéro de la revue ArcheoSciences – Revue d’archéométrie. Au-delà, nous exprimons quelques points de vue sur la pratique et la structuration actuelle et future de l’archéométrie en France. Plus largement nous questionnons la place et la nature de l’interdisciplinarité dans les différents volets des archéosciences.

The Raman effect is at the basis of Raman scattering and microspectrometry: in the first part of the chapter, it is very shortly exposed together with differences with infrared (IR) spectroscopy, and advantages and drawbacks of the technique. The importance of the choice of the excitation wavelength, of the spectrometer (fixed, portable and handheld) and of the optics is underlined, while the information provided by the technique for inorganic and organic materials is considered. The surface-enhanced Raman spectroscopy (SERS) theory and principle applications are also taken into account. In the second part of the chapter, all the different applications of Raman and SERS to cultural heritage materials are contemplated: minerals, gemstones, rocks, patinas and corrosion products, glass, pottery, mortars, dyes, binders, resins, paper, parchment, inks and human remains. For each category of objects, the answers that Raman microspectrometry and SERS can give to the archaeometric and conservation-related questions, the in situ investigations, the search of specific spectral parameters and the use of chemometrics are shown, together with the most recent advances in the field.

A Raman study of a Sèvres soft paste (frit) porcelain plate allowed the identification of both the crystalline and amorphous phases. Cristobalite and pseudowollastonite gave main Raman signatures in the body where also tridymite, amorphous alkali silicate glass and lead arsenate apatite were detected. Na0.4K0.1Ca0.5Pb4(AsO4)3 lacunar apatite is identified as opacifier in blue and green overglaze enamel. Pb-Sb-reach pyrochlore (Naples Yellow) pigment was found in yellow and green overglaze enamels. The orange hue is obtained by superposing a hematite bearing red paint stroke over the yellow. These results are compared to those previously obtained by detailed OM, SEM, XRD and XRF analyses. Some of the phases identified by XRD (quartz, tridymite) are hardly detected by Raman and vice versa cristobalite was not found by XRD, most probably due to its low amount.

Abstract : Medieval wall painting fragments, taken at the medieval Mosque of al-Qarawiyyin in Fez, have been investigated by means of X-ray fluorescence and UV-Vis-NIR diffuse reflectance spectroscopies. The analyses permitted to determine the palette of pigments used by craftsmen of the time...

The laurel-leaf points of the Volgu cache found in eastern France rank among the most remarkable examples of skilled craftsmanship known from the Solutrean period of the Upper Palaeolithic. In addition to pressure flaking, heat treatment may have helped in the making of the points, as both have been previously described in association with Solutrean assemblages. This study presents the results of an infrared spectroscopic analysis of seven artefacts from the Volgu cache conducted to test this assumption. The findings show that heat treatment was not universally applied to this particular tool type, meaning that we must rethink the reasons why such a technique was used.