As a gold producer, Mexico is relatively unimportant since it produces less than 200,000 ounces annually. Lead and Zinc Lead and zinc deposits are so widely distributed throughout Mexico that it is beyond the scope of this paper to describe even the most important districts. Lead ores are generally present in combination with other minerals containing zinc, silver, and minor amounts of gold. The states of Chihuahua and Zacatecas, from colonial times, have accounted for more than 70 percent of national production. In 1970, Mexico produced 266,400 metric tons of zinc and 176,600 metric tons of lead. Anarch, Penoles, and Minera Frisco are the traditional producers of these metals. Sulfur Sulfur production in 1970 declined to 1.3 million metric tons from 1.7 million metric tons a year earlier, and exports were reduced to 661,000 tons. Moreover, the price of Mexican sulfur has declined sharply in the face of severe world competition. The largest sulfur producer in Mexico is Azufrera Panamerican S.A., which is 66 percent government owned. In line with government policy, the company recently announced a new marketing program with export quotas and an export sales price of $26.00 per long ton, effective January 1, 1972. Fluorspar Since 1956, Mexico has been the world's largest producer and exporter of fluorspar, accounting for 90 percent of shipments to the United States. Several new planned expan-sions entailing an aggregate investment of more than $50 million are under way, and by 1971 production is expected to exceed 1 million tons annually with a value of approxi-mately $32 million. The six major fluorspar producers in order of importance are: Cia. Minera las Cuevas, S.A. (affiliated with Noranda Mines Ltd.). Fluorita de Mexico, S.A. (Continental Ore Corp.) Fluorita de Rio Verde, S.A. (Continental Ore Corp.) Cia. Minera Rio Colorado, S.A., (Allied Chemical Corp.) Minerales Pennsalt, S.A. (Pennsalt Chemicals Corp.) La Dominicia, S.A. (Dow Chemical Corp.) Mexico's fluorspar deposits are mainly in the Sierra Madre Oriental of eastern and central Mexico, the Sierra Madre Occidental of western Mexico, and the Sierra Madre del Sur southwest of Mexico City. More than two-thirds of the deposits are in limestones of early Cretaceous age. The others are chiefly in shale or volcanic rocks that overly the limestone, or within or very near the intrusive Tertiary rhyolite. Typically, the deposits occur as nearly flat manto or blanket bodies or as steeply dipping veins, pipes, conical bodies, tabular and irregular replacements, and collapsed breccias. Indicated reserves in selected districts total approximately 15 million tons of fluorspar averaging about 65 per-cent CaF2.* * A survey of the principal fluorspar districts of Mexico was made in 1960 by the U.S. Geological Survey, in cooperation with Consejo de Recursos Naturales No Renovebles. The report on this survey is on open file. 37