Micro‐Raman spectroscopy and ancient ceramics: applications and problems

Abstract

Micro-Raman spectroscopy is applied for the study of two classes of ancient ceramic artefacts showing different features and technological background, i.e. the fine-grain Black Gloss Ware from Motya (Sicily, Italy) and the coarse-grain pottery from Khirbet al-Batrawy (Jordan). The characterization of the mineralogical composition of these ceramics allows exploring the firing conditions and the manufacturing process. In particular, μ-Raman spectroscopy permits to define the mineralogical assemblage of the bulk of both groups of ceramic samples as well as the nature of the black gloss and superficial decorations. Moreover, μ-Raman spectroscopy, allowing the identification of mineral phases in traces and describing as a consequence a more detailed mineralogical assemblage, can contribute to address issues concerning the provenance of the raw materials. The evaluation of the Raman results compared to those obtained by optical microscopy, X-ray diffraction and electron microscopy highlights that Raman spectroscopy shows a great potential in the analysis of coarse-grain and low fired ceramics, whereas it proves its limits in the analysis of fine and vitrified pottery class where the intergrowth of glass and crystalline phases provides Raman spectra not so easily interpretable.

Technological fingerprints of the Early Bronze Age clay figurines from Tell Mardikh-Ebla (Syria)

“…In addition, it is needful to explore how the vessels were formed and decorated on the surface and their conditions of firing [20,39,40].…”

The ceramics of Malpaís of Zacapu, Michoacán, Mexico, during the Early and Middle Postclassic periods (900–1450AD): Micro-chemical characterization of surface paintings

“…Previous studies by photoacoustic spectroscopy in Aztec ceramics from 1325 to 1521 AD revealed an absorption peak around 530 nm characteristic of earth sienna pigment (Fe 2 O 3 · (n H 2 O) + MnO 2 · (n H 2 O) + Al 2 O 3 ). This study was carried out in combination with EDS technique Spectrochimica Acta Part B 119 (2016) [10][11][12][13][14][15][16] that confirmed the presence of iron in the pigment under analysis [5]. Other analytical studies were carried out on Maya ceramics from Guatemala and Honduras neighbouring countries, but none has been conducted on Tarascan ceramics [6,7].…”

“…The investigation of organic and inorganic pigments is the dominant issue in the ceramic analysis using Raman spectroscopy. This technique allows the identification of crystalline and amorphous compounds, and the discrimination of the mineral phases without the interference of matrix signal [6,[12][13][14]. Nevertheless the fluorescence effect in Raman spectroscopy may hamper the identification of the pigments characteristic bands and in these cases XRD could represent a good complementary tool although limited to the identification of crystalline compounds.…”

Raman Spectroscopy of cultural heritage Materials: Overview of Applications and New Frontiers in Instrumentation, Sampling Modalities, and Data Processing

“…Studies of the pigments used for ceramic glazes in soft paste, hard paste and majolica ceramics have been the subjects of numerous articles and are extensively reviewed elsewhere [68,84,86,87,90,125,258]. For the ceramic paste, the identification of mineral phases, especially in traces, offers a more detailed characterisation of the mineralogical assemblage, leading to the identification of the raw materials used, which can then contribute to illuminating clues about their provenance [204]. Additionally, the characterisation of the mineralogical composition reveals clues to the firing conditions (temperatures reached, firing atmosphere) to document the manufacturing process.…”