426 



UNITED STATES MINERAL RESOURCES 



to acids and oxidation at ordinary temperatures. It 

 has a high thermal conductivity and good electrical 

 conductivity. 



The principal uses of molybdenum are in the iron 

 and steel industries with 70 percent of the apparent 

 consumption going into high-speed, tool, stainless, 

 and low-alloy construction steels and 20 percent 

 going into special alloys and castings; the remain- 

 ing 10 percent is used as molybdenum metal and in 

 pigment, catalysts, agriculture, chemicals, and 

 lubricants. 



It must be evident from the above list of uses 

 that molybdenum is an essential metal in a highly 

 sophisticated industrialized nation such as the 

 United States and that it is equally essential in 

 other industrially developed countries. The extent 

 to which our present living standards depend on 

 the ready availability and constant supply of mo- 

 lybdenum may be illustrated by an example of 

 molybdenum utilization in the automotive industry : 

 10 million units yearly production consumes more 

 than 2 million pounds of molybdenum, a significant 

 consumption despite the small weight of molybde- 

 num used per unit. 



Without molybdenum as an alloying metal, super- 

 strength steel as used in heavy construction such 

 as modern skyscrapers and bridges would be more 

 costly, and in some instances the increased weight 

 needed for equivalent strengths would render cer- 

 tain construction patterns unmanageable. 



Molybdenum can substitute for tungsten, vana- 

 dium, chromium, columbium, tantalum, nickel, and 

 boron. Each substitution is a matter of cost-avail- 

 ability to obtain certain desired qualities in the fin- 

 ished product. 



Molybdenum is virtually the sole metal commodity 

 of which the United States is a net exporter. Do- 

 mestic production in 1970 was just over 110 million 

 pounds of molybdenum, or two-thirds of the free 

 world production. Domestic consumption, on the 

 other hand, is about 50 million pounds; the United 

 States annually exports about 55 million pounds of 

 molybdenum in various forms such as molybdenite 

 concentrates, molybdenum trioxide, and ferromo- 

 lybdenum to more than 20 other nations. 



EXPLOITATION 



Recorded world production of molybdenum began 

 just after 1900, when about 100 short tons of the 

 metal was produced, approximately half of which 

 came from Australia and Norway and half from the 

 United States (Fischer and King, 1964). Through 

 the years, molybdenum has been produced, at one 

 time or another, in some 30 countries around the 



world. The major part, however, has come from 

 nine countries: the United States, Chile, Canada, 

 Japan, Korea, Norway, Mexico, the U.S.S.R., and 

 China, 



The United States currently supplies about 60 

 percent of the world's total molybdenum; Canada, 

 about 15 percent; the U.S.S.R. and China, about 

 15 percent; and all other producing countries, 10 

 percent. 



World production of molybdenum increased from 

 about 300,000 pounds per year in 1906 to 3 million 

 pounds per year in 1932, a tenfold increase during 

 this 26-year period. The next tenfold increase oc- 

 curred within a 5-year period in the 1930's, as a 

 result of a major increase in United States produc- 

 tion brought about chiefly by the initiation of large- 

 scale mining by block caving of the Climax ore 

 body in Colorado. Production increased sharply dur- 

 ing World War II to a high point in 1943 of 70 

 million pounds of molybdenum and then decreased 

 rapidly to about 24 million pounds in 1946, remain- 

 ing at this level until 1949 owing to the low level of 

 demand that followed the end of hostilities. Since 

 1949 a relatively uniform and consistent increase 

 in the annual rate of production, interrupted only 

 by recession in 1958 and work stoppages in 1962, 

 has continued to the present, at which time about 

 200 million pounds of molybdenum is produced 

 annually. 



Until 1936, domestic production of molybdenum 

 was as a main product of molybdenum ores. In 

 1936, at the Bingham, Utah, porphyry copper mine, 

 recovery of molybdenum as a byproduct was begun ; 

 today about one-quarter of the United States pro- 

 duction of molybdenum is obtained as a byproduct 

 of copper mining, and at least half of the world 

 production of molybdenum is obtained as a byprod- 

 uct or coproduct of copper mining operations. 



For many years the famous Climax molybdenite 

 mine in Colorado was the only known porphyry 

 molybdenum deposit in the world; but in 1957, the 

 Questa molybdenite deposit in New Mexico was 

 recognized to have many characteristics of a 

 stockwork-type ore body, and intensive exploration 

 confirmed the presence of a large tonnage of low- 

 grade molybdenite ore. In 1966, open-pit mining of 

 the disseminated ore body at Questa began, and by 

 1969, the annual production of molybdenum was 

 more than 10 million pounds. In British Columbia, 

 several porphyry molybdenum and copper-molyb- 

 denum deposits were developed, and in 1966, mo- 

 lybdenum output from British Columbia's mines 

 amounted to 20 million pounds. 



Early in the 1960's, intensive exploration was 



