Study of Pigments from the Colonial Convent of Actopan, Hidalgo, Mexico

In this work, scanning electron microscopy (SEM), X-ray diffraction (XRD), and infrared spectroscopy (FTIR) techniques were used to study blue, red, ochre pigments from wall paintings of the 16th century colonial convent San Nicolás de Tolentino in Actopan, Hidalgo, Mexico. blue pigments, nanometric fibers with a chemical composition mostly O, Si, Al, Mg identified. XRD FTIR analysis indicated presence palygorskite clay, which suggests that these analyzed are similar Mayan blue. red pigment, structures different morphologies (spines flake shapes, for instance), C, S, Ca, Na, Mg, K higher concentration Fe Pb, observed. Complementary showed color originates hematite lead. Finally, pigment significant O Fe, was associated goethite mineral, while calcite crystalline phase identified all pigments; show characteristic known Mexican Colonial palette.