Tezoantla Tuff («Cantera de Tezoantla», Hidalgo state): the first Mexican "Heritage Stone"

Abstract

The Tezoantla Tuff («Cantera de Tezoantla» in Spanish) was designated as a 'Heritage Stone' by the International Union of Geological Sciences on October 22, 2022, under revised criteria that were approved the same year, being the first in Mexico and the second to be awarded a volcanic tuff. It is a volcanic ash tuff of Miocene age, with lowtemperature argillic hydrothermal alteration (zeolitization), that has been quarried for at least 400 years in the municipality of Mineral del Monte of the Comarca Minera UNESCO Global Geopark. Due to its aesthetic value (in particular, the white variety) and suitable physical properties, this stone has been used as building and sculpture material in notable monuments of Baroque, eclectic and Neoclassical styles of the state of Hidalgo and the historic center of Mexico City, most of which are cataloged in different lists of cultural heritage. In addition, it has been widely used in vernacular architecture and in industrial constructions that are part of the outstanding mining heritage of the geopark, with Cornish engine houses (19th century) standing out.