1899

Asarco organized as American Smelting and Refining Company. Included in original consolidation were mines and mining claims in Colorado and Mexico. Major plants in consolidation included: Globe by-products plant (Denver, Colorado), East Helena lead smelter (Montana), El Paso lead plant (Texas).

1901

Merged with M. Guggenheim’s Sons. Included in the merger were the Perth Amboy copper refinery (New Jersey) and smelters in Mexico (Chihuahua lead smelter, San Luis Potosi lead and copper smelter, Monterrey lead and copper smelter). Acquired five additional mines in Mexico.

1910

Purchased mining properties in Silver Bell district of Arizona. Copper smelters built in El Paso, Texas, and Hayden, Arizona.

1922

Amarillo, Texas, zinc plant constructed.

1942

Corpus Christi, Texas, zinc plant constructed.

1954

Production commenced at Silver Bell, Asarco’s first open-pit copper mine.

1960

Southern Peru Copper Corporation opened the Toquepala mine and Ilo smelter.

1961

Mission copper mine in Arizona started up.

1967

Mexican mines and plants reorganized as Asarco Mexicana, S.A., and 51% interest sold to Mexican investors.

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.

1983

Hayden copper smelter modernization completed.

1985

Corpus Christi zinc smelter and refinery operations suspended indefinitely.
Pima copper mine in Arizona acquired.

1986

Ray copper mine and smelter purchased.

1987

Anamax interest in Eisenhower mineral reserves acquired.

1988

Encycle, Inc. started up waste treatment facility at Corpus Christi.

1989

IMASA Group acquired.
49.9% interest acquired in copper mining business of Montana Resources, Inc.
Asarco announces decision to end involvement in coal mining.
Asarco announces board approval to expand copper facilities at Mission and Ray mines and El Paso smelter.

1991

Expansion of Mission mine completed.

1992

Expansion of Ray mine completed.
Asarco becomes a fully integrated copper producer.

1993

Modernization of El Paso smelter completed.

1994

Acquisition by Southern Peru Copper Corporation of Ilo Refinery.
Underground operation at Mission mine announced.
Asarco and Coeur d’Alene Corp. form Silver Valley Resources, Inc.

1995

Asarco purchases an additional 10.7% interest in SPCC, increasing holdings to 63%; consolidates results.
SPCC starts SX/EW facility at Toquepala.
New sulfuric acid plant started at SPCCs Ilo smelter.

1996

Asarco announces construction of a new mining and SX/EW facility at Silver Bell mine.

1997

Silver Bell solvent extraction/electrowinning facility started.
Asarco sells shares in Grupo Mexico, S.A. de C.V. for $323 million.
Expansion program started at SPCC’s Cuajone mine; to increase mine’s production 50%.

1999

Asarco celebrates a century of operations as American Smelting & Refining Company.
Asarco suspends operations at El Paso, Texas copper smelter.
Asarco closes its Black Cloud Mine in Colorado.
Asarco exchanges interest in Coeur and Galena mines for interest in Coeur d’Alene Mines Corp.
Grupo Mexico purchases shares of Asarco for $2.2 billion (including debt); retains Asarco as wholly-owned

             U.S. operating subsidiary.
Asarco Sells its Stake in the Troy, Montana Mine and Rock Creek Project to Sterling Mining Company
Grupo Mexico Sells Asarco’s Specialty Chemicals Division, Enthone-OMI for $503M

2000

Grupo Mexico Sells American Limestone Company to CSR America for $211M.
Grupo Mexico Forms Americas Mining Corporation (AMC) to include Asarco, SPCC and Minero Mexico, to be headquartered in Phoenix, Arizona.

2001

Asarco suspends operations at East Helena, an original M. Guggenheim facility.
Asarco suspends operations at the Tennessee Mines Division.
Asarco reduces mine production at Mission by 61 percent.
Asarco reduces refined copper production at Amarillo by 29 percent.
Asarco relocates its corporate headquarters to Phoenix, Arizona, leaving New York City after 102 years in lower Manhattan.

2002

Asarco reduces mine production at Mission to 15% of total capacity.

2003

Asarco sells its interest in SPCC to AMC.

2005

Asarco files Chapter 11 Proceedings for five non-operating, dormant subsidiaries.
Asarco files Chapter 11 Proceedings on August 10th.

2006

Asarco closes the Globe (Denver) High-Purity Metals plant; the last of the original M. Guggenheim facilities.

2008

Sterlite Industries Agrees to Purchase ASARCO for $2.6 Billion; later withdraws bid.

2009

Asarco Emerges from Bankruptcy and Re-integrates into Grupo Mexico