1971
Four Tennessee zinc mines purchased.
1973
San Xavier copper mine and leach plant in Arizona started production
1974
ASARCO Mexicana, S.A. reorganized as Industrial Minera Mexico, S.A. and 15% interest sold to Mexican investors reducing equity to 34%.
1975
Corporate name changed to ASARCO Incorporated. Amarillo zinc refinery closed. Amarillo copper refinery commenced production.
1976
Southern Peru Copper Corporation opened Cuajone copper mine.
1978
Industrial Minera Mexico, S.A. (IMM) reorganized. ASARCO owns 34% of Mexico Desarrollo Industrial Minero, S.A., a holding company formed to hold shares of IMM and shares of certain IMM operating subsidiaries.
1979
Modernization of El Paso Plant completed. Eisenhower Mining Company, a partnership of Anamax and ASARCO, began mining the Palo Verde copper deposit located between ASARCO’s Mission and San Xavier copper mines