In the study of cultural heritage, most of the analytical techniques are point-specific or give information about small areas of the object. Therefore it is essential to obtain an overview of which points are suitable for these further investigations. To fulfill this, a first imaging study is the best way to proceed. Hereby, we can record the entire piece at once and observe the behavior and relation between different materials of the object. Various types of light can be used to obtain a selection of images and consequently also different information about the artifacts. Among them, infrared (IR) photography can be used as a first analysis, for instance, to reveal the pigments’ response upon interaction with IR radiation.

In following we will present results obtained via IR video-photography on a selection of painted objects from the Mexican cultural heritage. These items are analyzed by False Color procedure, where colors are assigned to every grey tone of the pure IR photo. Hereby it is possible to distinguish between certain pigments on the painted surface.

Recently, a team of archaeologists discovered the existence of the oldest burial in a pyramid known to date in Mesoamerica. The tomb, referred to as Tomb 1, was discovered in Chiapa de Corzo, Chiapas, Mexico. In here, two skeletons were excavated along with a rich offering of green stone pieces, indicating their elite origin. The burial dresses consist of various necklaces, bracelets, belts, and anklets from which some beads were carved in the shape of gourds, monkeys, and alligators. Here we present a full, integrated methodology based on a variety of non-invasive and non-destructive analytical techniques, such as X-ray fluorescence (XRF), Raman, and Fourier Transform infrared (FT-IR) spectroscopy. These techniques are used to characterize and identify the minerals which were found in these burials. This information contributes not only to conservation and restoration purposes, but also gives more insights on the green stone (jadeite and other minerals) trading networks between different cultures in south Mesoamerica in the Pre-Classic period (c.a. 750 – 700 B. C.).

Over 2000 micro-X-Ray Fluorescence (μ-XRF) measurements of iron gall inks were collected at the General Archive of the Nation in Mexico (Archivo General de la Nación, AGN). The portable X-Ray system SANDRA permitted detection of common elements present in all iron gall inks (e.g. Ca, Fe, S, etc.) as well as characteristic traces and impurities (e.g. Cu, Ni, Zn, Pb, etc). The documents in the data set originate from all over Mexico and are dated between the 16th and 19th centuries. All manuscripts were well preserved.

Extensive statistical processing of the relative X-Ray intensities revealed common features in groups of documents with the same provenance. Among the findings, there is a progressive trend to complex mixtures from the beginning of the 16th century to the 17th. A reverse trend was observed for the following century. Zinc, lead and seldom arsenic, chromium and mercury seem characteristic for northern areas whereas manganese seems common to the vast majority of studied inks.

As a general concern in conservation research, special attention was addressed to copper, as it is known to have additive effects to the degradation of cellulose. This metal seems fairly common to Mexican inks, especially during 18th century.

To the best of our knowledge, this is the first examination taken to such a large number of inks. This study contributes to the more-focused development of suitable treatments that tailor specific needs, since they are to be based on of ink’s composition. It sets a precedent for the study of these inks in the Americas and allows conservators and historians to gain further insight into the history of their usage in Mexico.

La Blanca and Chilonche are two of the many Mayan settlements located on the lower reaches of the Mopan river (Department of Petén, Guatemala). The archaeological work conducted by La Blanca Project (University of Valencia, Spain) over the last ten years has revealed the rich polychrome of the monumental architecture of these sites, where the remains of ancient mural paintings are of the highest quality.

In order to ascertain the materials and techniques used by painters at each site throughout the Classic period, our research team has recently conducted an analytical study with a multi-technique approach based on the combination of several non destructive and micro-destructive instrumental techniques, namely, light microscopy (LM), scanning electron microscopy-X-ray microanalysis (SEM/EDX), transmission electron microscopy (TEM), voltammetry of microparticles (VMP), X-ray microdiffraction (mXRD), X-ray diffraction (XRD), UVeVis spectrophotometry, FTIR spectroscopy and gas chromatographyemass spectrometry (GCeMS). These instrumental techniques provide reliable and complementary data, such as elemental and mineralogical composition, the identification of functional groups as well as specialization studies of electroactive species.

This paper presents the results obtained at the Laboratories for the Analysis of Works of Art at the University of Valencia (Spain) and the Polytechnic University of Valencia (Spain) after chemically comparing the pigments and mural painting techniques of both Maya archaeological sites.

The Maya archaeological site of Ek’Balam is located in Yucatán, Mexico. This place is known for its artistic tradition of reliefs modeled in stucco as well as the rich pictorial and hieroglyphic texts. Although the mural played a key role in the artistic program architectural of elite groups, most of these remains have not been studied, either by its incomplete or fragile condition, or by localization in inaccessible substructures.

In this study, technical aspects of the mural paintings from rooms 12 and 50 of the main building of the site are addressed by the spectroscopic analysis of its materials. Optical microscopy was used to observe the layers superposition and pigment distribution, while the stucco and rock support were characterized by X-ray Diffraction (XRD) and X-ray Fluorescence (XRF). Moreover, the chromatic palette composed of different colors and tones of red, yellow, orange, green, blue and black were analyzed mainly with non-invasive techniques using Raman and FTIR spectroscopies as well as XRF.

The information obtained from the combination of these analytical techniques, allowed a better understanding of the similarities and differences between these two rooms that were built during the last construction stage of the Acropolis. These results were also compared with previous analyses of mural painting of this site and other Maya paintings.

As a result of archaeological investigations carried out in the pre-Hispanic city of Izamal, Yucatan, Mexico a large number of fragments of pottery vessels were recovered from the period known as maya protoclassic. The most important of this collection was its similarity to ceramic style representative recognized as Holmul, whose production has been identified mostly in the region of the Central Maya Lowlands. This style includes Ixcanrio Orange Polychrome ceramic type as diagnostic type more easily distinguished by its orange slip and tetrapods supports. Izamal, is the only place in the Northern Maya Lowlands has reported a large amount of pottery of this ceramic type. In this study we try to identify the origin of manufacture using X-ray diffraction technique. This will allow us to understand the social and political behavior of this ceramic tradition and their presence in this region of the Maya area.

Spectroscopy technique is used for various applications, for example in archaeology, in order to analyze samples of floors, including material excavation sites. In this work the floor samples that were found in two rooms belonging to a house in a residential Hispanic area, at different stratigraphic levels corresponding to the classical period, as well as samples that were collected in two deposits of lime (El Refugio and El Llano) around the site mentioned were analyzed. The characterization of the samples of the archaeological site Chingú in Tula de Allende in the state of Hidalgo was carried out by using Scanning Electron Microscopy (SEM) to observe the morphology of the samples and Energy Dispersive X-ray Spectroscopy (EDS) to analyze the composition of cementitious material of the floors and natural material of lime deposits. Comparing these samples with other archaeological works of literature, the morphology and composition of manufactured floors will be discussed.

The Huastec region was conquered by the Aztec Empire during the reign of Moctezuma I (1440-1469), nevertheless no objects from this important place have been found for sure in the offerings of the Great Temple of Tenochtitlan until now. In this paper the Huastec affiliation of some Tenochca shell objects is discussed based on its comparison with pieces found in the Huastec region, from the stylistic and technological perspective. For the technological study of the objects experimental archaeology and SEM analyses are used.

In the Great Temple at Tenochtitlan, the archaeologists found more than 150 offerings with thousands of pieces, most of them made on foreign raw materials to the Basin of Mexico. Among these votive contexts, the Chamber III of stage IVa (AD 1440-1469), buried during the government of Moctezuma I, is one of the most richness offerings of the temple. Inside this context, the quantity of greenstone beads is huge, and among them, there is a group of translucent appearance that resembles the green calcite objects from the Huastec region. The purpose of this research is to confirm or discard this probable cultural origin and technological manufacture of these beads. To do that, we perform different analysis with neither non-destructive nor invasive techniques like X-Ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), Raman, Optic Microscopy (OM), and Scanning Electron Microscopy (SEM). By this way we could confirm the similarities among Huastec pieces and these beads, both at mineralogical and technological levels. Based on that, and supported with some written sources from the Colonial period, we propose that these pieces could be war prizes and looted objects by pillage during the Aztec campaigns against Huastec sites; furthermore some of these goods were deposited as victory´s gifts to the gods at the Great Temple of Tenochtitlan.

At the Great Temple of Tenochtitlan, the archaeologists found hundreds of stone masks considered foreign pieces obtained by commerce, tribute, and pillage. Because of that, they were classified in the main Mesoamerican styles, like the Olmec, Mezcala, Teotihuacan, Mayan, Mixtec and Aztec art. Among them are seven Teotihuacan Style masks found in five offerings. Its presence was explained by other researchers as relics looted by Aztec people from the Teotihuacan site, because the Aztec priests and rulers employed them as sources of power, prestige and mythical links between the City of the Gods and Tenochtitlan. But, are these stone masks from Tenochtitlan really Teotihuacan items? How can we identify which of them came from Teotihuacan and could be relics and which of them not? To solve this problem, we analyze its manufacturing techniques and compare them with lapidary objects from different areas of Teotihuacan, employing experimental archaeology, Optic Microscopy and Scanning Electron Microscopy. As results, we identify two technological patterns: five masks share the tools and techniques of Teotihuacan manufactures but two other masks contrast with them. Interestingly, its technology match with the Tenochcan productions, so, both pieces could be recreations crafted by Aztec artisans during the Postclassic times.

Seventy six speckled greenstone items have been recovered on the surrounding structures of the Aztec precinct of the Great Temple of Tenochtitlan. Several researchers have identified the material as marble. Also, these objects have been labeled as Mixtec style due to the raw materials involved in their manufacture as well as their apparent similarity with other known Mixtec objects. The main objective of this essay is to determine the raw materials and the technology employed on its manufacture. Based on earlier composition analysis using Infrared spectroscopy (FTIR) and X-ray Fluorescence (XRF), it became clear that all items are made of the same calcite-serpentine mineral alloy, which probably comes from the Oaxaca region. It is interesting the homogeneity and standardization among these pieces by analyzing them with experimental archaeology and the characterization of their manufacturing traces. Comparing their raw material, morphology and techniques with those of Mixtec sites, the analysis revealed that they are not in fact related at all; however they do coincide with the manufacturing process of Tenochca (Aztec) style objects. This fact might point towards the actual origin of the raw materials, their obtainment and the technology behind the elaboration of luxury goods at Tenochtitlan.

The Flemish painter Simón Pereyns travelled to New Spain in 1566 as a member of the viceroyal court. In two important paintings La Virgen del Perdón (1568) and San Cristóbal (1588) we identified wide use of blue smalt pigment, a potassium glass with cobalt oxide. The color of this material depends on its manufacture process, from pale greyish blue to violet or dark blue. The more blue color the more expensive the pigment. On the 16th century market the commerce of smalt was divided into many categories based on the material quality. Historical archive documents testify smalt imports from Seville to New Spain in two different qualities: fine and smalt woody ashes. In Pereyns` paintings the smalt was used in specific parts of the composition as the dark sky in landscapes, shadows of draperies and under layers in order to create a color background for the figures. Nowadays, in these areas, the alteration of the paint layer is evident. The blue has been changed into brown color. Optical microscopy (MO), scanning and transmission electron microscopies were performed in order to characterize the particles of smalt. The degradation of potassium glass was verified, as a consequence of aging and degradation process due to environmental conditions. These phenomena are well known and study on European paintings. In this research our aim is to explore the intentional use of smalt on Pereyns’ compositions and how color change as a consequence of microscopic materials instability can influence the contemporary reception of the paintings. Many paintings from New Spain have a dull, dark and limited palette but the original was very different. The remarks about the color of New Spain's paintings should considered the normal aging of the paint components, studied by materials science and art history.

Outstanding information about the material composition and pictorial techniques of the New Spain Colonial painting can be obtained via a full characterization using a set of analytical techniques. Given the cultural importance of this painting, a non-invasive approach is preferred. Moreover, the preparation and use of reference materials using original recipes is necessary for a correct interpretation of the spectroscopic data from historical objects. Here, we present the results obtained via an in-situ Raman spectroscopic analysis of a set of pictorial reference materials, created according to XVI and XVII centuries’ recipes. Several difficulties were encountered, such as the low Raman detection signal, an intrinsic fluorescence of the material, and in some cases even laser-induced degradation. For this reason, the usual molecular Raman analysis was extended to Surface Enhanced Raman Spectroscopy (SERS), which enhances the Raman signal and quenches the fluorescence. It was then applied to the analysis of two wood paintings from the ex-convent San Francisco Tepeyanco, in Tlaxcala.

The altarpiece dedicated to San Antonio de Padua was made of wood assembled and self-supporting structure attached to the wall. It is a straight plant altarpiece designed to withstand sculptures. This master piece belongs to the a set of Baroque altarpieces preserved in the state of Campeche and is located in San Roque Church in the City of San Francisco de Campeche, Mexico. This altarpiece was decorated following the traditional technique of the seventeenth century in Mexico, a technique derived from Spain. According to literature sources we know that the strata are the wood, the imprimatura, the pictorial strata and metal sheets that make the golden color and corladuras. The characterization of the constituent materials was of great importance for the interpretation of the constructions system and manufacture of the decoration. The present study shows the results of analysis techniques such as optical microscopy, Particle Induce X Ray Emission (PIXE), and X Ray Florescence Spectroscopy (XRF) and interpretation of the different layers constituting the altarpiece of San Antonio.

The colored component of several important ancient pigments, including Egyptian blue and Han blue, are based on alkali earth copper tetrasilicate materials. In recent work, we have found that these layered materials can be chemically exfoliated into their constituent monolayers to provide alkali earth copper tetrasilicate nanosheets—defined by nanometer thickness and lateral dimensions that are on the order of several microns. The facile exfoliation of these materials into nanosheets is especially surprising in view of their long history on artifacts under a variety of environmental conditions, and we have examined the issue of whether archaeological samples are affected by this exfoliation mechanism. We have characterized the properties of these nanosheets by an array of analytical techniques, including powder x-ray diffraction, photoluminescence measurements, and Raman spectroscopy. In all cases, we observe differences between nanosheet and bulk samples that originate from the loss of coupling between layers when going from three-dimensional to two- dimensional structures. Both CaCuSi4O10 nanosheets (derived from Egyptian blue) and BaCuSi4O10 nanosheets (derived from Han blue) have strong near-infrared luminescence properties like their bulk counterparts, yet they are amenable to modern solution processing methods. We have demonstrated ink jet printing with CaCuSi4O10 nanosheet inks, as well as the fabrication of nanosheet-based papers. Potential applications for these materials include NIR-based biomedical imaging and security inks.

Coahuilite, a new variety of amber is described from the Late Cretaceous Olmos Formation (ca. 73 Ma.), Coahuila, north of México. This amber is totally distinct chemically and stratigraphically from the Miocene Chiapas amber (ca. 23-13 Ma.), Southern México, which according to mineral nomenclature is currently known as Simojovelite var. nov. Additionally, an emended description of Bacalite is proposed, based on the physicochemical analysis and geological record of a fossil resin recently recovery from the Late Cretaceous El Gallo Formation (ca. 73 Ma.), Baja California, northwestern México. The results are supported by characterization of such ambers using synchrotron-based Infrared (FTIR) microspectroscopy.

During an archaeological rescue on Tula’s southwestern urban settlement, two zoomorphic pendants made of the nacreous bivalve Pinctada mazatlanica were found. Such elements belong to a residential compound dedicated to the production of prestige goods for the elite at the Toltec capital.

The importance of these objects analysis lies on the fact that both are on-site taxidermy renderings of two canines. This essay main purpose is to identify the biological zoomorphic renderings and its character, since it’s possible that the samples were not living animals but a depiction of their hides. This research will also analyze the manufacturing technology of these pendants using experimental archaeology, Optical Microscopy and Scanning Electron Microscopy, which indicate a local production controlled by the ruling class.

The Archaeological Site La Pintada is located near Hermosillo, Sonora, Mexico; this is one of the most important sites in the region due to its extension and wide archaeological evidence. This site was a gathering point for various indigenous groups since the pre-Hispanic age to the first contacts with the Spanish conquerors; they left their live experiences and worldview in the form of rock paintings along a wide natural canyon. Several of these paintings are in risk due to weathering processes of their rock support: the volcanic tuff.

In order to preserve these paintings the characterization of the volcanic tuff was made with petrographic analyses and X-Ray Diffraction, and among with the results obtained from environmental monitoring, different degrees of alteration were established. According to these results, the conservation treatment proposed was the consolidation of the tuff.

The consolidants used for this treatment were alkoxysilanes in two variations: Silicate and alumino-silicate which were developed in Mexico for volcanic tuff consolidation. The consolidants were synthetized in the laboratory, and afterwards were tested on powders and cubic probes of the rock in Hermosillo’s environmental conditions (24°C, 45%RH).

The consolidants were tested in two different types of application: aspersion and injection. The consolidated probes were evaluated for hardness, water absorption and color change. Afterwards, in situ tests were performed. The results of this evaluation showed that the Silicate consolidant was the best for this treatment, since it was easy to manipulate, improved the rock’s properties and did not cause a change appearance; making this Mexican material suitable for the conservation of the rock paintings.

This contribution shows the results of a study carried out in order to determinate the deterioration mechanisms suffered by stucco masks from the important archaeological Mayan site of Edzná, Campeche, México; due to their long exposition to the tropical environment of the zone. Stratigraphic analysis of fragments from the masks containing pigments and surface neoformation products, were analyzed by optical microscopy and scanning electron microscopy coupled to a secondary X-ray emission system. Crystalized salts mineral composition were characterized by X-ray diffraction. Also, during the study, environmental parameter like temperature and relative humidity were monitored in site. Results indicate that stuccos mineral matrix is formed by calcareous materials, covered by films with variable proportions of ferrous materials (red, ochre and yellow colors) and rich carbon content (black color). Compounds were associated to blue and green colors. Al these materials showed a high level of deterioration because of differential forces caused by stucco and deposits of environmental soluble salts during dissolution crystallization cycles caused by humidity differences between stucco and environmental as a consequence of their particular exposure conditions.

In this study electrochemical and surface analysis were carried out in order to provide preliminary information to diagnose the state of conservation of two bronze bells from two Colonial religious building from San Francisco de Campeche City: The Cathedral of Nuestra Señora de la Purísima Concepción and the Ex-temple of San José. Small corroded bronze samples were retired from each bell and analyzed by using optical microscopy in order to observe the distribution of the oxides over metal surface. Complementary XRD analysis was used to identify crystalline phases formed as a consequence of bells interaction with the urban tropical environment of this city. Electrochemical techniques such as linear polarization resistance (Rp) and potentiodynamic curve (CP) were conducted “in situ” in order to evaluate the behavior of bell bronze patinas under the action of two artificial solutions that recreate typical electrolyte formed over corroded metal surfaces in urban environments.