minerals Article Study of Pigments from the Colonial Convent of Actopan, Hidalgo, Mexico Jesús Benjamín Ortega-Lazcano 1 , Demetrio Mendoza-Anaya 2 , Eleazar Salinas-Rodríguez 1 , Juan Hernández-Ávila 1 , Otilio Arturo Acevedo-Sandoval 3 and Ventura Rodríguez-Lugo 1,* 1 Área Académica de Ciencias de la Tierra y Materiales, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca 42184, Mexico; [email protected] (J.B.O.-L.); [email protected] (E.S.-R.); [email protected] (J.H.-Á.) 2 Instituto Nacional de Investigaciones Nucleares, Ocoyoacac 52750, Mexico; [email protected] 3 Área Académica de Química, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Pachuca 42184, Mexico; [email protected] * Correspondence: [email protected] Abstract: In this work, scanning electron microscopy (SEM), X-ray diffraction (XRD), and infrared spectroscopy (FTIR) techniques were used to study blue, red, and ochre pigments from wall paintings of the 16th century colonial convent of San Nicolás de Tolentino in Actopan, Hidalgo, Mexico. In the blue pigments, nanometric fibers with a chemical composition of mostly O, Si, Al, and Mg were identified. XRD and FTIR analysis indicated the presence of palygorskite clay, which suggests that these analyzed blue pigments are similar to Mayan blue. In the red pigment, structures with different morphologies (spines and flake shapes, for instance), with a composition of C, O, Al, Si, S, Ca, Na, Citation: Ortega-Lazcano, J.B.; Mg, and K and a higher concentration of Fe and Pb, were observed. Complementary analysis showed Mendoza-Anaya, D.; Salinas- that the red color originates from hematite and lead. Finally, the ochre pigment showed a significant Rodríguez, E.; Hernández-Ávila, J.; presence of O and Fe, which was associated with the goethite mineral, while calcite was a crystalline Acevedo-Sandoval, O.A.; Rodríguez-Lugo, V. Study of phase identified in all analyzed pigments; these show that these pigments are characteristic of the Pigments from the Colonial Convent known Mexican Colonial color palette. of Actopan, Hidalgo, Mexico. Minerals 2021, 11, 852. https:// Keywords: Actopan; colonial; Hidalgo; microstructure; pigments doi.org/10.3390/min11080852 Academic Editors: Domenico Miriello and Adrián Durán Benito 1. Introduction From prehistoric times, people have sought to represent and transmit beliefs, cul- Received: 30 June 2021 ture, religion, and what happened in the environment, preserving what is beneficial and Accepted: 3 August 2021 essential for survival and well-being [1,2]. In this respect, mural painting has played an im- Published: 7 August 2021 portant role in the history of Mexico because through it, we can learn many facts regarding pre-Hispanic life, the development of the Spanish conquest and colonization, and the inde- Publisher’s Note: MDPI stays neutral pendence and the modern life of Mexico. In particular, mural paintings made in religious with regard to jurisdictional claims in convents immediately after the Spanish defeated native warriors in Tenochtitlan Mexico published maps and institutional affil- contributed in an important way to the consummation of the conquest of Mesoamerica iations. and the conformation of the New Spain, and, at the same time and in a subtle manner, a new religion (Christianity) was imposed with the decoration of religious images on the walls and other available areas in the convents [3]. The friars intended to save all those having different customs; their main interest was to show the Christian God and give them Copyright: © 2021 by the authors. salvation for their souls [4]. Painting was used as a means of evangelizing because through Licensee MDPI, Basel, Switzerland. the pictures, it was easier to introduce the indigenous people into the History of Salvation This article is an open access article and that Jesus Christ is the only way to Heaven and to eternal life; otherwise, committing a distributed under the terms and mortal sin without performing proper penance leads directly to “hell” [4–6]. conditions of the Creative Commons The earlier mural paintings were made by the fresco technique by anonymous artists Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ with careful monitoring by the monks. The raw materials used to elaborate these earlier 4.0/). paintings had a regional origin and were categorized as organic, inorganic, and synthetic [7]; Minerals 2021, 11, 852. https://doi.org/10.3390/min11080852 https://www.mdpi.com/journal/minerals Minerals 2021, 11, x FOR PEER REVIEW 2 of 19 Minerals 2021, 11, 852 2 of 16 The earlier mural paintings were made by the fresco technique by anonymous artists with careful monitoring by the monks. The raw materials used to elaborate these earlier thepaintings first were had a obtained regional fromorigin vegetablesand were categorized and animal as organic, sources, inorganic, for example, and synthetic indigo and cochineal.[7]; the first The were second obtained were from mainly vegetables manufactured and animal from sources, minerals for such example, as iron indigo oxide, yellow-and ochrecochineal. silty The clays, second cinnabar, were mainly and green manufactured earth. Synthetic from minerals colorants such were as iron obtained oxide, yel- by the combinationlow-ochre silty of clays, organic cinnabar, and inorganic and green colorant earth. materials,Synthetic colorants for example, were Mayanobtained blue by the [8]. combinationNowadays, of organic it is possible and inorganic to appreciate colorant the materials, historical for and example, artistic Mayan beauty blue of the [8]. mural paintingsNowadays, in colonial it is possible convents, to whichappreciate are mainlythe historical located and in artistic central beauty Mexico. of the An mural example ispaintings the Augustinian in colonial ex-monasteryconvents, which of are San mainly Nicol locatedás Tolentino in central in Mexico. Actopan An in example the State is of Hidalgothe Augustinian (Figure1 ex-monastery) and at its open of San chapel, Nicolás which Tolentino is the in largest Actopan open in chapelthe State in of Mexico. Hidalgo The Augustinian(Figure 1) and Order at its founded open chapel, this conventwhich is inthe 1546; largest the open building chapel is attributedin Mexico. toThe Fray Augus- Andrés tinian Order founded this convent in 1546; the building is attributed to Fray Andrés de de Mata. Its cover is in a plateresque style, and its cloister combines Gothic and New Mata. Its cover is in a plateresque style, and its cloister combines Gothic and New Spain Spain styles. From an architectural and pictorial point of view, the former convent of San styles. From an architectural and pictorial point of view, the former convent of San Nicolás Nicolás de Tolentino constitutes one of the greatest examples of New Spain art of the 16th de Tolentino constitutes one of the greatest examples of New Spain art of the 16th century, century, as seen in Figure1, for which it was declared an Historic and Artistic Monument as seen in Figure 1, for which it was declared an Historic and Artistic Monument of the of the Nation, by means of the Decree of February 2, 1933, issued by the Government of the Nation, by means of the Decree of February 2, 1933, issued by the Government of the Mexican Republic [9]. Mexican Republic [9]. FigureFigure 1.1. (a()a Geolocation) Geolocation map map of the of state the of state Hidalgo of Hidalgo Mexico at Mexico the coordinates at the coordinates 20°16′06″ N 2098°56◦16′03506″00 N W; (b) geolocation map of the convent of San Nicolás de Tolentino at the coordinates 20°16′6.24″ N, 98◦5603500 W; (b) geolocation map of the convent of San Nicolás de Tolentino at the coordinates 98°56◦ 0′34.800″ W; (c)◦ the0 main00 facade of the convent of San Nicolás de Tolentino; and (d) samples of 20mural16 6.24 paintingsN, 98 from56 34.8the convent:W; (c) geometric the main facadethemes of the barrel convent vault of (left) San Nicoland theás garden de Tolentino; of Eden and (d(right).) samples of mural paintings from the convent: geometric themes of the barrel vault (left) and the garden of Eden (right). Wall painting is a first-hand source of knowledge about religious thought in New SpainWall as the painting images ishave a first-hand been used source in different of knowledge instances, such about as religiousfor pedagogical thought means, in New Spainas well as theas cult images objects have [10]. been Known used inas different “grutescos” instances, in Spanish, such asthe for adjective pedagogical form means, “gro- as welltesque” as cult is also objects used, [10 which]. Known combines as “grutescos” in an identifiable in Spanish, way the the adjective absurd, formcontradictory, “grotesque” isunreal, also used, illogical, which and combineslaughable in[11]. an The identifiable syncretization way theof Spanish absurd, art contradictory, with Mexican unreal,art illogical,turned the and grotesque laughable into [11 what]. The was syncretization also called “tequitqui,” of Spanish with art a with color Mexican palette different art turned thefrom grotesque the Spanish into one, what such was as also the called use of “tequitqui,” smoke black, with grana a color cochineal palette red, different and indigo from the Spanishblue [12]. one, such as the use of smoke black, grana cochineal red, and indigo blue [12]. Unfortunately,Unfortunately, the the colonial colonial paintings paintings show show a high a high level level of deterioration, of deterioration, which whichis as- is associatedsociated with with environmental environmental and andhuman human factors. factors. For this For reason, this the reason, analysis the and analysis charac- and characterizationterization of historic of historic vestiges vestiges making making use of useall available of all available tools that tools provide that provide any kind any of kind ofinformation information about about these these will will be valued be valued [13].