'Copper mining in Arizona', a state of the
United States, has been a major industry since the 1800s. In 2006
Arizona was the leading
copper-producing state in the US, producing a record five billion dollars worth of copper. Copper mining also produces
gold and
silver as byproducts. Byproduct
molybdenum from
copper mining makes
Arizona the nation's second-largest producer of that metal.
Although copper mineralization was found by the earliest
Spanish explorers of Arizona, the territory was remote, and copper could not be profitably mined and shipped. Early Spanish, Mexican, and American prospectors searched for gold and silver (see ''
Silver mining in Arizona''), and ignored copper. It was not until the completion of the
Southern Pacific Railroad in 1876 that copper became broadly economic to mine and ship to market.
Underground mining of rich copper veins was used until the early 20th century. After the
Bingham Canyon mine in
Utah successfully mined a large low-grade copper deposit from a large open pit, the same technique was applied to Arizona’s
porphyry copper deposits. Arizona's first open pit copper mined opened at
Ajo in 1917.
Jerome
Native Americans used copper minerals of the Verde district at modern-day
Jerome as pigment to decorate skin and textiles. The first European to visit the area is thought to be Spanish explorer
Antonio de Espejo, who found silver at a location in central Arizona in 1583. No mining resulted, and
Juan de Oñate led a another expedition searching for Espejo’s silver location in 1598; many claims were staked, but the expeditioners returned to
Santa Fe without mining any silver, and the deposits remained unexploited.
[1]
The United Verde mine exhausted the rich oxidized ores in 1884, and the mine closed.
William A. Clark of Montana visited the district in 1888, bought it, and reopened the mine. The smelter at
Clarkdale was built in 1915.
[2]
Ajo
Spaniards mined on a small scale at
Ajo as early as 1750. After the
Gadsden Purchase brought the southern
Arizona into the
United States in 1853, Americans reopened the mine in 1855.
Clifton-Morenci
Prospectors found copper in the Greenlee district at
Morenci in 1872, and began producing in 1873.
Bisbee
An army scout noted copper mineralization in the Warren district at present-day
Bisbee in 1877. Production began in 1880 after a rich discovery of copper carbonate on the Copper Queen claim. The success of the Copper Queen mine convinced
Phelps Dodge to buy the adjacent Atlantic claim in 1881.
Phelps Dodge later bought control of the Copper Queen and adjacent claims. The company started mining the
Lavender Pit in the early 1950s.
[3]
Globe-Miami
Silver mining started at
Globe in 1874. The silver mines shut down in 1877, but the following year copper mining took over.
[4]
White Mesa district
The White Mesa copper-mining district is in the western part of the
Navajo reservation, 112 mile northeast of
Flagstaff, in
Coconino County. The copper deposits consist of
malachite and
chrysocolla as grain coatings in the
Jurassic Navajo Sandstone. They were first mined on a small scale by Mormon settlers in the 1800s, then briefly in 1917, and again 1939-1941. The district produced about 550,000 pounds of copper and a small amount of silver.
[5]
Copper mining today
As of 2006, there were 11 producing copper mines in Arizona.
★
Cochise County: Bisbee mine;
★
Gila County: Pinto Valley mine and Miami mine;
★
Greenlee County: Morenci mine;
★
Mohave County: Mineral Park mine;
★
Pima County: Mission mine, Silver Bell mine, and Sierrita mine;
★
Pinal County: Ray mine and Tohono mine;
★
Yavapai County: Bagdad mine.
Six of the mines are owned and operated by
Phelps Dodge, three by
Asarco, and one each by
BHP Billiton and
Mercator Minerals.
[6]
In addition to its existing mines,
Phelps Dodge is preparing its new Safford Mine, eight miles north of the town of
Safford in
Graham County to begin producing copper in 2008. The Safford mine, in a large
porphyry copper deposit, will be the largest new copper mine put on production in Arizona in more than 30 years.
[7]
External links
★
Arizona Department of Mines and Mineral Resources: ''Arizona's Metallic Resources Trends and Opportunities 2007''
★
Phelps Dodge Mining Co.
★
ASARCO
★
Mercator Minerals Ltd.: ''Mineral Park''
References
1. Richard T. Moore and George H. Roseveare (1969) ''Silver'', in ''Mineral and Water Resources of Arizona'', Arizona Bureau of Mines, Bulletin 180, p.254.
2. C.A. Anderson (1969) Copper, in Mineral and Water Resources of Arizona, Arizona Bureau of Mines, Bulletin 180, p.117-156.
3. C.A. Anderson (1969) ''Copper'', in ''Mineral and Water Resources of Arizona'', Arizona Bureau of Mines, Bulletin 180, p.117-156.
4. Horace J. Stevens (1909) ''The Copper Handbook'', v.8, p.172-173.
5. Charles B. Read, R. D. Sample, and H. H. Sullwold Jr. (1943) ''Copper Deposits of the White Mesa Mining District, Coconino County, Arizona'', US Geological Survey, Open-File Report 43-24.
6. N. Niemuth, ''Arizona'', Mining Engineering, May 2007, p.67.
7. Russell A. Carter, ''Safford moves toward startup'', Engineering and Mining Journal, June 2007, p.46-48.