0000000000917935
AUTHOR
María Teresa Doménech Carbó
Characterization of Maya Blue Pigment in Pre-Classic and Classic Monumental Architecture of the Ancient Pre-Culombian City of Calakmul (Campeche, Mexico)
This paper presents the first evidence of the use of Maya Blue pigment in late pre-classic (c.300BC-300AD) architecture in the Maya Lowlands. This was detected combining an innovative technique, the voltammetry of microparticles (VMP), with atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy/energy dispersive X-ray microanalysis (SEM/EDX), visible spectrophotometry and Fourier transform infrared spectroscopy (FTIR). The pigment was found on the polychrome facade of substructure IIC of pre-Columbian city of Calakmul (Campeche, Mexico). The identification of Maya Blue in this building may prove to be the earliest known use of this colour on the …
Microfocus X-ray computed tomography analysis of corroded glass objects
Abstract Microfocus X-ray computed tomography (µCT) is a useful tool for non-destructive analysis of corroded archaeological glass objects and for monitoring restoration and conservation processes for these materials. This was demonstrated by µCT analysis of artificially corroded laboratory-produced glasses and corroded archaeological glasses retrieved from soil environments. Corrosion layers with a thickness of 20 µm or more can be detected as areas with lower X-ray attenuation values than the non-corroded glass. Features that are revealed by µCT analyses include the degree and patterns of corrosion and the presence of various internal structures in the corrosion layers. The study of resto…
Estudio del biodeterioro en resinas alquídicas usadas como aglutinante en pinturas modernas mediante espectroscopía FTIR y pirólisis-cromatografía de gases-espectrometría de masas (Py-GC-MS).
Evaluation of the alteration produced by microbiological attack on alkyd resins has been carried out by FTIR spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS). The latter included the online derivatisation of alkyd resins using hexamethyldisilazane during pyrolysis. Specimens consisting of thin films of resins formed on glass slides were used. Analyses performed on the specimens in which different genera of bacteria and fungi were inoculated and allowed to grow, indicate that the attack of microorganisms encourages the scissioning of the polymeric resins and the appearance of short-chain fatty acids. IR bands ascribed to carboxylic acids appearing in samples from in…
Aportación de nuevas metodologías multitécnica en el estudio y conservación de patrimonio numismático de procedencia subacuática
Este trabajo presenta un estudio del estado de conservación de monedas con base de cobre procedente del Museo Nacional de Arqueología Subacuática. La metodología multitécnica incluye instrumentación convencional como microscopía óptica, espectroscopia FTIR y técnicas avanzadas nanoinvasivas como voltamperometría de micropartículas y haz de iones focalizados-FESEM-EDX. Así se ha podido identificar el tipo de aleación, productos de corrosión, depósitos superficiales y antiguas intervenciones. Cabe señalar la identificación de mecanismos de alteración atípicos como la formación de complejos carboxilados de iones metálicos generados en los procesos electroquímicos de corrosión del metal o aleac…
Preparation of body colors in Pre-classical Maya culture: the red pigment in the 19th tomb (Peten, Guatemala)
The pigments were important in the funerary customs of the ancient Maya. They could be introduced as an offering inside the tombs or burials, and were also used to wrap the dead bodies, as if it were a funeral shroud. In the tombs and burials of royalty and high social classes the use of pigments for this purpose is well documented, and physicochemical studies are focused on their identification. This scientific contribution shows the results obtained when analyzing two reddish pigmenting materials from the grave goods of the tomb 19 of the archaeological site of Rio Azul, (Guatemalan Department of Petén), using a multi-technique approach including microscopy, diffraction, spectroscopic, el…
The Maya Blue Pigment
Abstract Maya blue is an artificial pigment fabricated by the Maya in the early first millennium AD. The pigment was used in Prehispanic times from the southern Maya region to most Mesoamerican cultures. Maya blue is made from indigotin mixed with palygorskite. This light blue pigment is surprisingly resistant to degradation in adverse environmental conditions, as it is unaffected by the attack of acids, alkalis, oxidants, reducing agents and organic solvents. Scientists do not fully agree in the mechanism of this organoclay interaction. The fabrication and distribution of this pigment probably required a sophisticated technical and commercial infrastructure. This chapter reviews the presen…