Molybdenum mining in the United States

Last updated
United States primary molybdenum production, 1920-2014 (date from USGS) US Molybdenum Production 1920-2014.png
United States primary molybdenum production, 1920–2014 (date from USGS)
Usa edcp relief location map.png
Red pog.svg
Climax
Red pog.svg
Henderson
Red pog.svg
Questa
Red pog.svg
Bagdad
Red pog.svg
Sierrita
Red pog.svg
Thompson Creek
Red pog.svg
Mission
Red pog.svg
Bingham Canyon
Molybdenum mines

Molybdenum mining in the United States produced 65,500 metric tons of molybdenum in 2014, worth US$1.8 billion. The US was the world's second-largest molybdenum producer, after China, and provided 25% of the world's supply of molybdenum.

Contents

The US was a major exporter of molybdenum; net exports made up 48% of US production. Because most molybdenum is used as a steel alloy, demand for, and therefore the price of, molybdenum, tracks the demand for steel.

As of the end of 2014, the United States had 2.7 million tons of molybdenum reserves, and 5.4 million tons of identified molybdenum resource. [1]

Molybdenum mines

Molybdenum is produced in the US from porphyry deposits of two types. The first class, which produces molybdenum as the primary product, includes molybdenum porphyry deposits. In 2014, three such molybdenum porphyry deposits were mined: two in Colorado and one in Idaho; the mine in Idaho was put into inactive status at the end of 2014. The second class, which produces molybdenum as a byproduct of copper mining, includes copper porphyry deposits. In 2014, byproduct molybdenum was produced at ten porphyry copper mines, in Arizona, Montana, Nevada, and New Mexico. Byproduct molybdenum from copper mines accounted for 47% of US molybdenum production in 2013.

In both molybdenum porphyries and copper porphyries, the molybdenum is present as molybdenite.

Climax mine, Colorado

Climax Mine, 2007 CLIMAX MOLYBDENUM MINE, COLORADO.jpg
Climax Mine, 2007

The Climax mine, historically the world's largest source of molybdenum, is north of Leadville, Colorado. Climax first produced molybdenum in 1915, and was worked continuously from 1924 until it was shut down in 1995. Formerly an underground mine, the Climax mine reopened as a surface mine in 2012. It is owned by the Climax Molybdenum Company and now operates as an open pit.

Henderson mine, Colorado

The Henderson molybdenum mine is just east of the snow-capped continental divide, which appears in the background (photo taken in mid-July, 2009) HendersonMineCO.jpg
The Henderson molybdenum mine is just east of the snow-capped continental divide, which appears in the background (photo taken in mid-July, 2009)

The Henderson molybdenum mine, near Empire, Colorado, started producing molybdenum in 1976, and was the nation's leading molybdenum producer in 2013, with 13,600 metric tons of molybdenum. The mine is owned by Climax Molybdenum Company

Thompson Creek mine, Idaho

The Thompson Creek mine, in Custer County, Idaho, is owned by the Thompson Creek Metals Co., Inc. The mine was a large producer in 2014, but was put on inactive status in December 2014. [2]

Byproduct of copper mining

As of 2014, there were ten US copper mines producing molybdenum as a byproduct. The number of mines producing byproduct molybdenum at any given time depends on the price of molybdenum and the amount of molybdenite in the ore.

Both copper sulfides and molybdenite are separated from the gangue by froth flotation. To separate the molybdenite from the copper sulfides, the copper/molybdenum concentrate is run through a molybdenite recovery flotation circuit, in which chemicals are added to "depress" the copper, meaning to prevent the copper sulfide minerals from attaching to the froth, while the molybdenum is unaffected. A few plants do the opposite, adding other chemicals to depress the molybdenum while the copper floats. [3]

Inactive ore deposits

There are a number of undeveloped and currently inactive molybdenum deposits in the United States.

Inactive mines

Deposits not yet mined

History

The United States dominated molybdenum production for most of the 20th century, producing more than half the world's production each year from 1925 through 1981. In 1953, US mines supplied 92 percent of world molybdenum production. [6] The US was the world's leading molybdenum producer from 1924 through 2006, after which US production was overtaken by China.

See also

Related Research Articles

Phelps Dodge Company

Phelps Dodge Corporation was an American mining company founded in 1834 as an import-export firm by Anson Greene Phelps and his two sons-in-law William Earle Dodge, Sr. and Daniel James. The latter two ran Phelps, James & Co., the part of the organization based in Liverpool, England. The import-export firm at first exported United States cotton from the Deep South to England, and imported various metals to the US needed for industrialization. With the expansion of the western frontier in North America, the corporation acquired mines and mining companies, including the Copper Queen Mine in Arizona and the Dawson, New Mexico coal mines. It operated its own mines and acquired railroads to carry its products. By the late 19th century, it was known as a mining company.

Molybdenite Molybdenum disulfide mineral

Molybdenite is a mineral of molybdenum disulfide, MoS2. Similar in appearance and feel to graphite, molybdenite has a lubricating effect that is a consequence of its layered structure. The atomic structure consists of a sheet of molybdenum atoms sandwiched between sheets of sulfur atoms. The Mo-S bonds are strong, but the interaction between the sulfur atoms at the top and bottom of separate sandwich-like tri-layers is weak, resulting in easy slippage as well as cleavage planes. Molybdenite crystallizes in the hexagonal crystal system as the common polytype 2H and also in the trigonal system as the 3R polytype.

Freeport-McMoRan Inc., often called Freeport, is an American mining company based in the Freeport-McMoRan Center, in Phoenix, Arizona.

Porphyry copper deposit

Porphyry copper deposits are copper ore bodies that are formed from hydrothermal fluids that originate from a voluminous magma chamber several kilometers below the deposit itself. Predating or associated with those fluids are vertical dikes of porphyritic intrusive rocks from which this deposit type derives its name. In later stages, circulating meteoric fluids may interact with the magmatic fluids. Successive envelopes of hydrothermal alteration typically enclose a core of disseminated ore minerals in often stockwork-forming hairline fractures and veins. Because of their large volume, porphyry orebodies can be economic from copper concentrations as low as 0.15% copper and can have economic amounts of by-products such as molybdenum, silver, and gold. In some mines, those metals are the main product.

Rheniite

Rheniite is a very rare rhenium sulfide mineral with the chemical formula. It forms metallic, silver grey platey crystals in the triclinic - pinacoidal class. It has a specific gravity of 7.5.

Polymetallic replacement deposit

A polymetallic replacement deposit, also known as carbonate replacement deposit or high-temperature carbonate-hosted Ag-Pb-Zn deposit, is an orebody of metallic minerals formed by the replacement of sedimentary, usually carbonate rock, by metal-bearing solutions in the vicinity of igneous intrusions. When the ore forms a blanketlike body along the bedding plane of the rock, it is commonly called a manto ore deposit. Other ore geometries are chimneys and veins. Polymetallic replacements/mantos are often stratiform wall-rock replacement orebodies distal to porphyry copper deposits, or porphyry molybdenum deposits. The term manto is from the Spanish word for mantle, or cloak, although the geologic manto is more like a mantle roll than a sheetlike structure.

Copper mining in the United States Review of the topic

Copper mining in the United States has been a major industry since the rise of the northern Michigan copper district in the 1840s. In 2017 the United States produced 1.27 million metric tonnes of copper, worth $8 billion, making it the world's fourth largest copper producer, after Chile, China, and Peru. Copper was produced from 23 mines in the US. Top copper producing states in 2014 were Arizona, Utah, New Mexico, Nevada, and Montana. Minor production also came from Idaho, and Missouri. As of 2014, the US had 45 million tonnes of known remaining reserves of copper, the fifth largest known copper reserves in the world, after Chile, Australia, Peru, and Mexico.

Gold mining in the United States Overview of gold mining in the United States of America

Gold mining in the United States has taken place continually since the discovery of gold at the Reed farm in North Carolina in 1799. The first documented occurrence of gold was in Virginia in 1782. Some minor gold production took place in North Carolina as early as 1793, but created no excitement. The discovery on the Reed farm in 1799 which was identified as gold in 1802 and subsequently mined marked the first commercial production.

Silver mining in the United States

Silver mining in the United States began on a major scale with the discovery of the Comstock Lode in Nevada in 1858. The industry suffered greatly from the demonetization of silver in 1873 by the Coinage Act of 1873, known pejoratively as the "Crime of 73", but silver mining continues today.

Silver mining in Nevada, a state of the United States, began in 1858 with the discovery of the Comstock Lode, the first major silver-mining district in the United States. Nevada calls itself the "Silver State." Nevada is the nation's second-largest producer of silver, after Alaska. In 2014 Nevada produced 10.93 million troy ounces of silver, of which 6.74 million ounces were as a byproduct of the mining of gold. The largest byproducers were the Hycroft Mine, the Phoenix Mine, the Midas Mine and Round Mountain.

Copper mining in Arizona Review of the topic

Copper mining in Arizona, a state of the United States, has been a major industry since the 19th century. In 2007 Arizona was the leading copper-producing state in the US, producing 750 thousand metric tons of copper, valued at $5.54 billion. Arizona's copper production was 60% of the total for the United States. 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 seldom be profitably mined and shipped. Early Spanish, Mexican, and American prospectors searched for gold and silver, 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.

Uranium mining in Utah

Uranium mining in Utah, a state of the United States, has a history going back more than 100 years. Uranium mining started as a byproduct of vanadium mining about 1900, became a byproduct of radium mining about 1910, then back to a byproduct of vanadium when the radium price fell in the 1920s. Utah saw a uranium boom in the late 1940s and early 1950s, but uranium mining declined in the 1980s. Since 2001 there has been a revival of interest in uranium mining, as a result of higher uranium prices.

New Cornelia mine Open-pit copper mine in Pima County, Arizona

The New Cornelia mine is a currently inactive open-pit copper mine in Pima County, Arizona, United States. It was the only productive mine in the Ajo mining district, and is located just outside the town of Ajo, which was built as a company town to serve the New Cornelia mines. The roughly circular pit is one and a half miles across at its widest point, and 1,100 feet deep at the center. Although not generally regarded as a 'dam', the New Cornelia Mine Tailings is often cited as the largest dam structure in the United States with a volume of 7.4 billion cubic feet.

Climax mine Mine in Colorado, United States

The Climax mine, located in Climax, Colorado, United States, is a major molybdenum mine in Lake and Summit counties, Colorado. Shipments from the mine began in 1915. At its highest output, the Climax mine was the largest molybdenum mine in the world, and for many years it supplied three-fourths of the world's supply of molybdenum.

Henderson molybdenum mine USA molybdenum mine

The Henderson molybdenum mine is a large underground molybdenum mine west of the town of Empire in Clear Creek County, Colorado, USA. The Henderson mine, which has produced molybdenum since 1976, is owned by Freeport-McMoRan.

Toquepala mine

The Toquepala mine is a large porphyry copper mine in the Tacna Province, Tacna Department, Peru. The mine is an open-pit mine producing copper, molybdenum, rhenium and silver with minor gold and zinc.

Los Pelambres mine

Los Pelambres mine is a copper mine located in the north-central of Chile in Coquimbo Region. It is one of the largest copper reserves in the world, having estimated reserves of 4.9 billion tonnes of ore grading 0.65% copper.

Sierrita mine Copper mine in Pima County, Arizonaa

The Sierrita Mine is a large copper mine located in the Sierrita Mountains of Arizona, in the southwestern part of the United States. The mine is located in southern Pima County, southwest of Tucson and west of Green Valley-Sahuarita.

Cerro Verde mine

The Cerro Verde mine is a very large copper mine located about 20 miles southwest of Arequipa, in southwestern Peru. Cerro Verde represents one of the largest copper reserves in Peru and in the world, having estimated reserves of 4.63 billion tonnes of ore grading 0.4% copper and 113.2 million oz of silver.

Sulfur production in the United States was 9.04 million metric tons of sulfur content in 2014, all of it recovered as a byproduct, from oil refineries, natural gas processing plants, and metal smelters. The United States was second in the world in sulfur production in 2014, behind China. The sulfur recovered was marketed in the forms of native (elemental) sulfur, and sulfuric acid. Total value was US$927 million in 2014.

References

  1. US Geological Survey, Molybdenum, Mineral Commodity Summary, 2015.
  2. US Geological Survey, Molybdenum in January 2015, Mineral commodity Survey, 2015.
  3. Joseph Shirley and Alexander Sutulov, "Byproduct molybdenite," in SME Mineral Processing Handbook, v.2 (New York, Society of Mining Engineers, 1985) pages 16–17 to 16–30.
  4. Desiree E. Polyak, Molybdenum, US Geological Survey, 2013 Minerals Yearbook.
  5. James R. Burnell, Colorado mineral and energy industry activities in 2007, Colorado Geological Survey, Information Series 77, 2007
  6. Historical statistics for mineral and material commodities in the United States, US Geological Survey, 2014.