In this paper, a novel hyperspectral image acquisition system able to obtain a set of narrowband images (~2,25 nm of bandwidth) and the related composition of monochrome images in the near-infrared is described. The aim of this system is to discriminate the materials by their optical spectral response in the range of 900-1700 nm. This system has been developed in the framework of a collaborative project that includes the improvement of the automatic composition of reflectographic mosaics in order to study the underdrawing of large formats big artworks in real-time. The main features of this project are detailed in this paper. Furthermore, a few enlightening results of the hyperspectral system and new lines of research are shown.

The necessity of studying cultural heritage through non-invasive and non-destructive techniques has led to significant advances in the last decade. One of the most recent advancements in this theme in Mexico is the portable X-ray system SANDRA, which was used to study three manuscripts directly related to the history of “San Nicolás Coatepec”, Mexico. X-ray fluorescence was chosen as the suitable technique because it can provide a fast qualitative and quantitative multielemental high sensitivity analysis. The documents were examined globally, using imaging techniques with UV and IR lighting. This research evinced a change in the composition and evolution of writing materials (inks and pigments) and provided information concerning historical use of the documents and its actual legal value as a property document. It also stressed the need of spanning these results to an extensive research attaining other regions of Mexico, in order to fully understand the Mexican documents particularities, aging and deterioration. This, in turn, will provide not only historical material information but also an invaluable scoop to understand deterioration and conservation issues.

This article discusses recent scientific research performed by the author in understanding the composition of archaeological purple pigments and dyes from molluskan sources, which were primarily used for the dyeing of royal and priestly textiles, as also cited in the Bible. Towards this end, the high-performance liquid chromatography (HPLC) method has been applied to the qualitative and quantitative multi-component fingerprinting of purple pigments extracted from various Muricidae mollusks inhabiting the Mediterranean waters. The results show that the colorants in these purple pigments belong to three chemical groups: the indigoids (of major importance), the indirubinoids, and the isatinoids. Application of this analytical method to purple pigments and dyes on archaeological artifacts from the ancient Near and Middle East has lead to a number of breakthroughs and discoveries made by this laboratory. These include the following: decipherment of the optimal method by which the ancients practiced purple-dyeing by completely natural means; first HPLC analysis of a raw unprocessed purple archaeological snail pigment and the resulting identification of a dibrominated indirubin in this pigment; discovery of the purple pigment as the sole paint pigment on a 2,500 royal marble jar from the Persian King Darius I; and the discovery that a 2,000 year old miniscule fabric found atop the Judean Desert palatial fortress of Masada belonged to the royal purple mantle of King Herod I and is the first Biblical Argaman dye found in ancient Israel.

Natural dyes have been extracted from both plants and animal to give color to textiles and handicrafts. This is the case of purple dye extracted from Justicia spicigera Schldt, an acanthaceae used as a color source since pre-Hispanic period in the Mayan area of Mexico and Central America. Spectroscopic (UV-Vis and FT-IR) and chromatographic (PY-GC/MS) techniques were employed in order to characterize some of their chemical properties. UV-VIS absorption spectra indicates a λmaxpeak at 581 nm, value associated to anthocyanins group under bathochromic effect. On the other hand, a structural characterization realized by FT-IR and Py-GC/MS indicated the presence of polar hydroxibenzoic acids and phenolic compounds which are characteristics of the molecular structure of anthocyanins.

This paper discuss the presence of powdered glass and quartz integrated in the red lake layers of two paintings attributed to the Sevillian painter Bartolome Esteban Murillo that belongs to the Guadalajara’s Regional Museum’s art collection. A laboratory experimental reproduction of the Sevillian painting technique was made using three different lakes (cochineal, madder lake and brazilwood) mixed with four varieties of glass to explore the optical properties and the influence of the transparent and translucent aggregates into the oil paint layers. The experimental reproductions were analyzed using ultraviolet-visible spectroscopy, optical and fluorescence microscopy and scanning electron microscopy (SEM-EDX). A comparison between the originals and the reproduced red lakes layers was carried out to understand the artistic process of Murillo’s color application. Preliminary results suggest that glass was not used as a siccative agent as the historical treatises mentioned but mainly as an additive to increase brightness, thickness and color saturation of the red lake layers related to the artist’s intention.

Xavier Guerrero (1896-1974) had an important role in the so-called Mexican Mural Renaissance, as a technical leader in the murals painted by Roberto Montenegro and Diego Rivera in the early 1920’s. Jean Charlot, Diego Rivera and David Alfaro Siqueiros considered him as a sophisticated fresco craftsman, whose knowledge came from a popular mural painters guild.

In 1941 the Mexican Government donated a School to Chillan, a Chilean town almost destroyed by a strong earthquake. David Alfaro Siqueiros and Xavier Guerrero were commissioned to paint murals on the Mexico School. Between 1941-1942 Guerrero decorated several walls and the staircase ceiling, the mural program is called De México a Chile (From Mexico to Chile). In 2010 another earthquake destroyed part of the ceiling. This study is part of the diagnosis project of De México a Chile, and consists in the characterization of the mortar and painting layers with optical microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermal analysis (TGA), while textural properties of the mortars were studied with nitrogen adsorption-desorption techniques.

Analytical results show a stratigraphic sequence composed of several layers of Portland and lime combinations, and also an interesting painting technique that possibly involves the Portland cement setting process, with the development of specular gypsum.

The analyses of work traces in the shell objects found in the offerings of the Great Temple of Tenochtitlan, by scanning electron microscopy (SEM), has allowed to find an important group of objects made locally in Tenochtitlan. These shell pieces have been found in the constructive stages IVb to VII (1469-1520). Recently, another groups of objects have been found that present different work traces and that seems to be foreign productions. In this paper this new data will be presented and it will be discuss the possible origin of the objects.

Tamtoc is a very important archaeological site in San Luis Potosi, in the Central region of Mexico. The pre-Hispanic Huastec culture developed in this site (900-1100 A.D.). During the archaeological excavations, a large amount of lithic artifacts were recovered from burials and offerings. Among them, pieces of semitransparent crystalline objects of color blue, green, yellow and white and green stone pieces were discovered in one of the most important ceremonial precinct, inside a water reservoir of the monument 32 “The Priestess”. The aim of this work is to measure the composition of the artifacts for provenance study and to establish the manufacturing technique and tools used to produce them. For material analysis, a combined analysis involving X-ray Fluorescence (XRF) and Raman spectroscopy was applied. The main elements as well as some traces can be measured by XRF while the mineral identification can be established by Raman. The results indicate that most of the pieces are calcite with traces of rare elements.

On the other hand, experimental archaeology using a well established methodology of optical and electron microscopy examination of the manufacturing traces was applied. From this technological study the specific use of tools and materials were established for this site.

A comparative study of two blue pigment found in separate megalithic structures in Yucatán México is presented. The first sample (M1) is a piece of turquoise stucco discovered at the top of a building known as Structure-2 in the town of Dzilam González. The second sample (M2) is a residual blue powder that was contained in a Oxcum Café type ceramic vessel recovered in the rubble of the Kabul building in Izamal city. The interest in characterizing these samples increases with the possibility of finding in them evidence of Maya Blue, a dye created in the eighth century by the Maya people, whose extraordinary physical and chemical properties have been studied in laboratories around the world. Maya Blue was a tailored technology used for several centuries, even during the Spanish occupation, throughout Mesoamerica. Despite 80 years of study, the mysteries of its composition, traditional preparation and obsolescence have not yet been fully resolved. Using different spectroscopic techniques (SEM, EDX, XRD, FTIR, UV-Vis DR) we have studied and compared the blue colorants in M1 and M2. Results indicate that M1 is Maya Blue. Despite some similarities in the infrarred vibrational spectra of the two samples, we have determinated that M2 is not Maya Blue but a non-Mesoamerican mineral pigment known as Ultramarine which was probably introduced to America by Europeans.

During the excavations made at a burial of the post-Classic Mayan period (1220-1521 A.D.) in the pyramid number 2 of the pre-Hispanic site of Lagartero, Chiapas, Mexico, a set of four small metallic artifacts depicting reptile’s heads, were recovered. The objects were in poor conservation conditions and were taken to the Metal Conservation Laboratory of the National School of Conservation (ENCRyM- INAH) for suitable cleaning and conservation treatments.

Analyses allowed identifying important technological features such as gilding remains. The analytical techniques included optical microscopy followed by X-Ray Fluorescence Spectroscopy (XRF), and Scanning Electron Microscope-coupled with Energy Dispersive Spectrometer (MEB-EDS). For the elemental depth profile a combined Particle X-Ray Emission Spectroscopy and Rutherford Backscattering Spectrometry (PIXE–RBS) analysis was carried out.

The results indicate that the objects are made of a copper alloy, and then gilded probably using electrochemical replacement gilding (thickness has less than 1 μm). This technology has been observed in other metallic objects recovered from the Chichen-Itza Cenote in Yucatan, but it was not available in Mesoamerican areas so far. So, it could imply that these artifacts might have been imported from South American areas.

Chemical-technology investigation was carried out for 95 belt sets from the burials of 8th−11thcenturies. In its course three groups of burials were separated on the basis of archaeology-statistical features; the Group 3 was identified as status one. All the groups contain belt sets made from the cooper-based alloys which include silver (6.98−92.87%) and amalgam. The major scheme of the belt sets (Groups 1, 2, 3) production is casting in moulds with print of used plaques; there are belt sets in Groups 1 and 2 which were made in different way (lost wax casting, casting in moulds with print of special matrix, forging). Chemical and technology parameters of the belt sets from the elite burials of the Group 3 are similar to the parameters of the belt sets discovered in the common burials of the Groups 1 and 2. There are a number of burials in the Group 1 the belt sets of which according to their chemical-technology characteristics could be attributing to the “award”.

This work shows current research on lithic raw material used by the ancient Maya of Toniná. The core of the city of Toniná lies on a steep-sided hill of calcareous sandstones from the shallow marine deposits dated as Oligocene, in the Chiapas Highlands of Southern Mexico. Results of paleontological fieldwork in Toniná show several biostrome sediments mound-like with tabular bafflestones and large coquina flagstones, which are sheet-like rocks enriched with fossil mollusk shells, corals, encrusted organisms, and calcareous debris. The people of Toniná intentionally selected and carved these rocks for use as building blocks and bricks on floors, walls, and stairways. At least two coquina flagstones measuring about 1.90 m long were identified in an archeological context most likely associated with carved stelae. Also non-marine carbonate rocks such as a crudely banded travertine and spongy calcareous tufa from recent sediments of freshwater environments surrounding Toniná were used by the Maya as a raw material on walls, columns, reliefs and murals base.

Results of the chemical, mineralogical and micromorphological analysis on plaster and bedding mortars from the walls of Toniná display a slightly interbedded lime of sparry calcite cemented in a highly porous groundmass with silt-to pebble-size of calcareous and siliciclastic rock-crushed aggregates, sand, and soil remains. Lime fabric reveals enclosing quartz grains, granular calcite crystals, and carbonaceous inclusions which may suggest that the lime has been made from a burnt grain-rich limestone with fibrous cement and porous microfabric. WDX analysis in lime lumps of plaster reveal an average amount of 1.37 wt% MgO associated with a limestone source ranging from regular to a magnesium-enriched limestone (1 to 2 wt %). XRF detect a strontium-rich level in the calcite matrix of plaster which is as high as that of fossil shells, tufa, and coquina. Finally, XRD shows that the mean amount of calcite in plaster is 95 wt% and lower amount (2-2.5w%) of siliciclastic minerals: quartz and albite. In contrast, calcite in mortar ranges less than 90.1 wt%. The concentrations of non-carbonate minerals, such as quartz and albite, are higher than those in plaster because mortar incorporates more siliciclastic rock remains, sand and clay.

Contemporary Art has the characteristic of being made with a wide diversity of materials. In this plastic age many of the artists employ polymers to create their works, but do not consider the degradation that their art will suffer eventually.

This work presents the studies performed for improving the manufacture of a series of sculptures made of latex rubber that belong to the Museo Universitario Arte Contemporáneo (MUAC), UNAM, in Mexico City. These sculptures made by César Martínez are blow up and deflated continuously during their exhibition. Techniques such as Fourier Transformed Infrared (FT-IR), X-ray fluorescence (XRF) and Raman spectroscopies were used for characterizing the manufacturing techniques of the artist. Dynamical Mechanical Analysis (DMA) was carried out to correlate the mechanical properties with the raw materials.

These analyses provide a comprehensive understanding of the material and the main factors that affect the degradation of the pieces. The combination of these studies made possible to suggest a new methodology to the artist in order to improve the quality and therefore enlarge the lifetime of his work.

In four offerings of the Great Temple of Tenochtitlan five groupings of Pinctada Mazatlanica shell pendants were found. Due to the burial conditions, damages on the surfaces can be observed in almost all the objects. In order to assess the deterioration degree, we used a visible light spectrometer. This is an inexpensive method to determine qualitatively the reflectance of the light at the surface that is directly related to the amount of organic material remains in these objects. This data may be used as a conservation marker for monitoring the collection and it can provide outstanding information to preserve the fragile shell pendants using a non-destructive method.

Tropical climate create ideal conditions for the development of microbial communities associated with biodegradation of historic buildings made with stony materials. This is the case of Fort San Carlos, a historic colonial building representative of military tendencies during the XVII century in San Francisco de Campeche City. In this study the Polymerase Chain Reaction (PCR), was used to identify microorganisms related with the biodegradation of its masonry structure. Specific primers for amplification of 16S and 18S ribosomal RNA genes were used for organisms identification by PCR. Amplification products were sequenced and after that compared with GENBANK nucleotide database using-BLASTn. Results indicated that microbial communities associated to biodegradation of the Fort San Carlos are bacteria from the Phyla Cyanobacteria, Proteobacteria and Actinobacteria.

The Santa Mónica Church is one of the most representative buildings in Guadalajara, Mexico as it is the finest Solomonic Baroque temple in the city. The church was built in the XVIII century with different types of volcanic tuffs, which have been studied from the macroscopic level to the structural level with the aim to determine the deterioration degree of the church’s tuffs.

Textural, morphological and structural properties of Tuff were characterized using X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR ATR) and 29Si and 27Al magic angle spinning nuclear magnetic resonance (MAS NMR), nitrogen adsorption-desorption techniques, scanning electron microscopy (SEM), thermo-gravimetric analysis (TGA), compressive strength tests were also performed.

Characterization data has provided a comprehensive view of the alterations on the volcanic tuff of Santa Mónica Church. Then the study focused on proposing the best strategy for the understanding and conservation of Churches and other buildings in Guadalajara which have been built with the same stone. Currently, siliceous materials doped with aluminum are being tested as consolidate.

Basalt chemical weathering can be related to chemical composition of both atmospheric dust and rainfall, in published works authors have shown that weathered basalt exhibits a raise in anions like sulfate, nitrate, phosphate, chloride and carbonate, and doing a follow up of rainfall chemistry during 2009 at downtown Puebla, it was shown that rainfall has not an acid pH because there is a strong contribution from atmospheric dust.

In this paper it is reported obtained results for dust samples collected during the dry season, collection was done in 3 places exposed to different environment, analysis of solid samples clearly reflect anthropogenic activities since the highest oil and grease content corresponds to a site with high population, also mineral carbonate amounts 30% in weight. An analytical sample was prepared and the filtrate used to measure pH which ranges from 6.3 to 7.84, and conductivity from 11.91-13.87 mS-cm-1. Main soluble ions range are as follow: sulfate 3.4-5.9 mg g-1, nitrate 0.19-0.54 mg g-1, chloride 0.7-8.91 mg g-1, sulfide 4-7 mg g-1, carbonate 304-364 mg g-1, this last correspond to 10% of the mineral content. Also, metals were determined as total (applying an acid digestion) and water soluble, obtained results allow to affirm that there are highly soluble metals like Ca, Pb (up to 97%), moderately soluble ones such as Cu and Mn (60% and 20% respectively) and non soluble ones like Al, Fe and Zn.

It was confirmed that atmospheric dust has all properties, which could produce an alkalinization of rainwater. Also, its water soluble ionic content can be a source for those ions causing basalt weathering.

Clays were used intensively in cultural heritage’s monuments and objects. Conservation procedures can be performed specifically for earthen materials using stabilized clays, considering that the aesthetic features must be preserved in order to avoid drastic differences and the lost of their patrimonial value.

This work presents the study of the mechanical behavior of clay stabilized with different materials following the norm ASTM D 6276 – 99a, for lime stabilization. The effects of other stabilizers on the clay were studied as well. For these purposes, lime, gypsum, Portland cement (type II), sodium hydroxide, and dehydrated cactus fibers of white cactus opuntia in concentrations of 2, 4, 6, 8 and 10 wt% were added to a clay from Morelia region.

Atterberg limits were determined to calculate the linear and volumetric stabilization. The best volumetric stabilization values were chosen to prepare samples to measure the mechanical behavior under compression, tension and flexion strengths. Colorimetric measurements were also performed on the stabilized clays to determine the best preparation with the most suitable aesthetic qualities to perform conservation treatments on monuments and cultural heritage constructions made with earthen materials.

The highest values for compression were observed for gypsum and mucilage additions while the highest tension was obtained for mucilage ones. Gypsum addition had the bigger rupture module under flexion. On the other hand, the color of the stabilized clay is closer to the original clay color for cement, lime and mucilage preparations.

This dietary study compares concentrations of trace elements in human skeletal series from the municipal cemetery of Xoclán, in Mérida, Yucatan, and a skeletal collection that was donated by the Yucatecan State Justice Department (PGH). The results from these modern samples are to be compared to those obtained from human collections from a colonial cemetery from Campeche and the pre-Hispanic Maya site of Xcambó. Our results indicate that the archaeological series show higher concentrations of Sr compared to the modern populations, both of which showed very similar values. Zn concentrations were similar when the modern values were compared to those derived from the colonial series from Campeche. Xcambó´s population, in turn, shows a high degree of variability in Zn values, which may be due to diagenetic contamination.

Xaltocan used to be an island located North of the Basin of Mexico in the bed of the lake of the same name, the occupation of which has been continuous for 1100 years. The area’s environment includes the island, the lake and the shore Xaltocan saline land and deep alluvial soil, the foothills and mountains, areas that provide different resources, whose exploitation is clear from the Paleoethnobotanical remains recovered from archaeological excavations.

Maize, basic resource in the daily life of Xaltocan, was also affected by sociopolitical and economic circumstances, so, it is possible that a different type of maize was used in each period of the locality. This is the interesting point to characterize morphometrically the maize from a context housing for the early Postclassic. To do so requires the application of different techniques (methodical process) to get to the characterization of corn: sample, flotation, separation and identification, measurement of corn through a microscope that could be complemented with electron microscopy scanning (SEM) to reveal possible microstructure.

In the measurement technique applied to the samples, the cob is divided into different sections; all of them can be measured, element by element, with a stereoscopic microscope for subsequent statistical analysis.

The study includes 231 sediment samples, distributed in 19 different depths and areas inside and outside of two dwelling domestic units. From 31,230 macrorremains, 6,140 were identified as Zea mays.