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

Abstract

Tarascan ceramic sherds from two Postclassical archaeological sites (900-1450 AD) at the Malpaís of Zacapu, Michoacán, Mexico, were investigated by combining Back-Scattered Scanning Electron Microscopy and Energy Dispersive Spectroscopy (BSEM-EDS), μ-X-Ray Diffractometry (μ-XRD), μ-X-ray Fluorescence Spectroscopy (μ-XRF) and μ-Raman Spectroscopy. These sherds are famous for their forms and decorations although the composition of its raw materials remains so far unknown and focused only on the composition of the ceramic paste. For the purpose of surface decoration characterization, the pigments used in slips and paintings were identified as hematite, magnetite, amorphous carbon, graphite and lignite. Furthermore chemical and molecular structure determination allowed the identification of technological aspects such as the firing temperatures and atmospheres used in ceramics production.

All That Glitters Is Not Plumbate: Diffusion and Imitation of Plumbate Pottery during the Early Postclassic Period (AD 900–1200) at the Malpaís of Zacapu, Michoacán, Mexico

“…Second, there is at least one technique that was not transferred: the technique of dipping in the slip and achieving the shine purely by firing properties of the raw materials. Moreover, the slip "recipe" is different for the pottery produced in Chiapas (with an iron and alumina base, completed by sodium, potassium, copper, and zinc; Neff 2001Neff , 2002aNeff , 2010Shepard 1948) than for the specimens from Zacapu (use of graphite; Jadot et al 2016).…”

“…Analyses by X-ray fluorescence (XRF), X-ray diffraction (XRD), and Raman spectroscopy were conducted on a sherd from UT52 (CPP437) as part of a more general study of the ceramic pigments used on the Malpaís de Zacapu. The results showed the use of graphite, associated with a carbon deposited by smoking, at the end of the firing process, giving a shiny and metallic aspect to the surface of this sherd (Jadot et al 2016). The graphite was applied on the surface of the pottery before burnishing, perhaps by rubbing a solid graphite mass (plumbago) on the surface (see Balfet et al 1992:123).…”

Gamme de chaux dans les économies anciennes. Méthodes de prélèvement et d’identification des types de chaux dans les fours (DRX, MEB-EDS, pétrographie) (Antiquité, Moyen Âge, époque moderne)

“…Ce dioxyde de silicium impur apparaît à 1 470 °C à partir d'éléments argileux, mais peut se former, sous certaines conditions, à partir de 1 050 °C (Gualtieri et Bertolani, 1992). Ainsi, sa présence a été décelée dans les parois d'argile cuite d'un four de potier antique (Eramo et Maggetti, 2013), ainsi que dans des poteries cuites à haute température (Marengo et al, 2005 ;Lazzarini et Verità, 2015 ;Jadot et al, 2016). Par le passé, des exemples similaires ont permis de proposer des températures de cuisson.…”

An Energy-Dispersive X-Ray Fluorescence Spectrometry and Monte Carlo simulation study of Iron-Age Nuragic small bronzes (“Navicelle”) from Sardinia, Italy

“…Energy Dispersive X-Ray Fluorescence Spectrometry (EDXRF) is a non-destructive analytical technique with wide applications in several research areas including the Cultural Heritage/Conservation Science one [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Performing quantitative EDXRF analyses on archaeological and Cultural Heritage metallic artifacts is, however, particularly challenging due to their complex multi-layered internal structure.…”

“…"Layers" may include: a) the original metal and/or alloy substrate (gold, silver, bronze etc. ); b) surface patinas enriched in corrosion products (sulphides, oxides and/or chlorides compounds) due to attack by agents present both in the atmospheric and/or burial environments; c) protective treatments applied in past conservation interventions; d) soil derived incrustations from the archaeological burial environment [10][11][12][13][14]. In cases where the layered structure is not homogeneous, the separation between two or more adjacent layers is not well defined and/or when the layers are very thin, meaningful results on the bulk metal composition are even more difficult to obtain.…”