Copper And Molybdenum Essay
Copper and Molybdenum Deposits in the United States
Copper and molybdenum resources were not recognized as valuable commodities until economic needs demanded the collection and processing of these minerals in large amounts. The most expansive deposits of copper and molybdenum occur in massive low grade ores and are found in intrusive porphyry formations, although many smaller sized but higher grade ores are located in non-porphyry areas. The nation has abundant domestic copper ore reserves but because of many detrimental economic factors much of the copper used by the U.S. industry is imported. Molybdenum ore is profuse and exports of it are high to fulfill the needs of foreign demand. Copper was first used by people around 4000 B.C. …show more content…
The most common ore horizons are fragmentary and porous amygdular layers, flow- top breccias, and faults in the basalts and overlying carbonates containing deposits formed in the Proterozoic,
Triassic, Jurassic or Tertiary ages along a continental rift zone near a marine interface of a former equatorial position. These deposits include native copper and some silver in the flows and Cu2S minerals along the fractures. Copper distribution was regulated by the host rock permeability and fracturing of basalt flows and sedimentary beds. Some copper nuggets are found in stream beds due to weathering of the site. Michigan copper districts produced more than
5.95 million t of copper with an average grade of 1.48%, Kennecott accounted for about 618,000 t of this total. Skarn deposits occur in Carr Fork, Utah and Copper Canyon, Nevada. The former is a porphyry bordering the Bingham, Utah site while the latter is associated with barren stock. Copper Canyon is a skarn bordering a weakly mineralized granitic and breccia pipe intrusive, which invades carbonate strata, containing chalcopyrite, pyrite, and some hematite, magnetite,
Copper and molybdenum resources were not recognized as valuable commodities until economic needs demanded the collection and processing of these minerals in large amounts. The most expansive deposits of copper and molybdenum occur in massive low grade ores and are found in intrusive porphyry formations, although many smaller sized but higher grade ores are located in non-porphyry areas. The nation has abundant domestic copper ore reserves but because of many detrimental economic factors much of the copper used by the U.S. industry is imported. Molybdenum ore is profuse and exports of it are high to fulfill the needs of foreign demand. Copper was first used by people around 4000 B.C. …show more content…
The most common ore horizons are fragmentary and porous amygdular layers, flow- top breccias, and faults in the basalts and overlying carbonates containing deposits formed in the Proterozoic,
Triassic, Jurassic or Tertiary ages along a continental rift zone near a marine interface of a former equatorial position. These deposits include native copper and some silver in the flows and Cu2S minerals along the fractures. Copper distribution was regulated by the host rock permeability and fracturing of basalt flows and sedimentary beds. Some copper nuggets are found in stream beds due to weathering of the site. Michigan copper districts produced more than
5.95 million t of copper with an average grade of 1.48%, Kennecott accounted for about 618,000 t of this total. Skarn deposits occur in Carr Fork, Utah and Copper Canyon, Nevada. The former is a porphyry bordering the Bingham, Utah site while the latter is associated with barren stock. Copper Canyon is a skarn bordering a weakly mineralized granitic and breccia pipe intrusive, which invades carbonate strata, containing chalcopyrite, pyrite, and some hematite, magnetite,