Destructive Analysis using X-rays) developed at the Physics Institute of the UNAM, Mexico, for the study of Mexican cultural heritage collections. The X-ray fluorescence (XRF) SANDRA device can use 75 W Mo, Rh and W X-ray tubes and Amptek Si-PIN and Cd-Te detectors that are selected and combined depending on the elemental range detection requirements and the specific problem to be studied. In this paper, a full description and characterization of this system, sensitivities for the X-ray tubes and detectors as well as the detection limits are discussed. Examples of applications to technological studies on pre-Columbian metallic artifacts and analysis of color materials of ancient Mexican codex are shown.

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.

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Colonial mural painting developed in Mexico in XVI century after the conquest of the pre-Hispanic cultures following the evangelization process little information exists about the chronology of the paintings and workshops, the painters, the pictorial techniques or the materiality of this art work.In this work, we present the non-invasive methodology of study of the pigments and other components of nine mural paintings in three colonial Augustinian ex-convents located in Epazoyucan, Actopan and Ixmiquilpan, in the state of Hidalgo, central Mexico. These places were selected not only because of the inherent value and iconographic characteristics of the paintings, which date to the XVI and XVII century, but also because they are in the same region and are well preserved and in good condition. Then it is possible to compare their materiality and get new information to answer to some of questions related to these paintings.X-ray Fluorescence (XRF) and Raman spectroscopy were conducted using portable equipment on scaffolds after a global examination under ultraviolet light. We were able to distinguish between different pigments used for different colors such as vermillion, orpiment, and a copper pigment, for the bright red, gold yellow, and green, respectively. These pigments are characteristic of the known Mexican Colonial color palette. Apart from this, we also found the presence of indigo in the blues, minium, and cochineal. A first comparison among the mural paintings of the three sites indicates different palettes and painting periods.

In 2010, Mexico celebrates 200 years since the beginning of the Independence war that gave rise to the independent Mexican Empire in 1821, and afterwards to the Mexican Republic. This document had two original copies; one of them was lost in a fire at the beginning of twentieth century, while the second was stolen and finally returned to Mexico in 1960, after a long history of events. This document is kept in the General Archives of Nation (AGN), Mexico.The “Independence Act of the Mexican Empire of 1821” was written on paper using iron-gall inks. The document has two parts: a declaration and a set of 36 signatures of Iturbide and other people involved in establishing the Independence of Mexico.The non-destructive study of this document was carried out in order to answer several questions: legitimacy, composition of the materials (paper and inks), deterioration conditions and a possible sequence of writing and the signatures. For these purposes several in situ techniques were used: optical microscopy, ultraviolet and infrared light imaging, portable X-ray Fluorescence and Raman Spectroscopy. This work presents the main results of this analytical methodology applied to the Mexican Independence Act. The results indicate that several inks were used in the manuscript and that the paper has an aging consistent with a nineteenth century document. From these results, we consider that the document examined is genuine and not a copy or facsimile of the original act.