ABSTRACT
From 1921 to 1940, small coal companies proliferated in Mexico, with a few larger ones starting production. The cumulative coal produced was 32 million tons, most of which was coking coal from the state of Coahuila. Coal became increasingly more important after 1950, and the trend has continued as a result of the development of the iron and steel industry and the mining and metallurgy industries. Evaluation criteria within the iron and steel industry differ from one company to the next and even within the various governmental offices that explore for coal. The coal deposits in Coahuila are considered the most important, based on completed studies. There are two coal fields in this state: Sabinas, which extends as far as Monclova and is divided into several sub-basins, and the Fuentes-Rio Escondido basin, which probably extends from Piedras Negras to San Ignacio in the State of Tamaulipas.
