Copper And Molybdenum Deposits In The United States :: essays research papers

Copper and Molybdenum Deposits in the United StatesCopper and molybdenum resources were not recognized as valuablecommodities until economic needs demanded the aggregation and processing of theseminerals in large amounts. The most expansive deposits of pig bed and molybdenumoccur in massive low grade ores and are found in intrusive porphyry formations,although many smaller sized but higher grade ores are located in non-porphyryareas. The nation has abundant domestic copper ore reserves but because of manydetrimental economic factors much of the copper used by the U.S. industry isimported. Molybdenum ore is profuse and exports of it are high to save theneeds of foreign demand.Copper was first used by people around 4000 B.C. in the manufacture oftools because of its malleability and later became an important additive inharder, more useful metals such as bronze (copper+tin 2500 B.C.) and brass(copper+zinc 0 A.D.). The growth of copper merchandise in the United States hasbeen a rela tively recent occurrence. North American French explorers knew ofsources of native copper in the region of Lake Superior and the area natives hadcopper jewelry and ornamentation. Earnest copper mining began in Simsbury,Connecticut about 1709 and copper was actually exported to England after asource was discovered in New Jersey around 1719. In later times domestic copperresources did not satisfy national needs until the discovery of gold inCalifornia shifted the focus of mineral geographic expedition westward and strikes of richcopper ores occurred in Tennessee and the Cordilleran base regions. The CivilWar caused copper demand to increase greatly in order to manufacture cartridgesand keep goods, this resulted in the openings of numerous copper mines ofwhich more than 90% were in the Lake Superior area giving an important advantageto the Union armies. Major copper production districts then shifted to Montanaand Arizona in the early 1890s. Production increased to reach peak levels o f900,000 tons a year during World War I and in 1970 1,600,000 tons of copper wereproduced but recent levels are lower, fluctuating between 1-1.5 million tons ayear. Technology has aided in increase production efficiency wich resulted inspectacular resource development in the U.S. and around the world.Molybdenum has been a major mineral since 1898 when it was discovered toharden poise as an additive and useful in compounding chemicals and dyes.Substantial mining began in 1900 in the southwest but the demand was so low that military action ceased in 1900. In 1906 the molybdenum industry boomed and with thedawn of WWI the need for quality steel further increased the necessity for this