UNITED STATES MINERAL RESOURCES 



BISMUTH 



By J. W. Hasler, M. H. Miller, and R. M. Chapman 



CONTENTS 



Abstract of conclusions 



Introduction 



Exploitation 



Geolo^c environment 



Geochemistry 



Bismuth ores 



Major sources 



Minor occurrences 



Resources 



Identified resources 



Hypothetical and speculative resources 



Prospecting techniques 



Problems for research 



References cited — , 



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ABSTRACT OF CONCLUSIONS 



In the United States, bismuth is largely a byproduct from 

 ores of other metals with which it is associated, principally 

 lead and copper. Lesser amounts of bismuth are found in 

 molybdenum, gold, silver, tin, tungsten, and zinc ores. The 

 United States consumes annually as much as four times the 

 amount of bismuth recovered from domestic ores; thus, the 

 United States must rely on imports for 50-75 percent of its 

 supply. The three principal uses of bismuth in the United 

 States at present are in the manufacture of pharmaceuticals 

 (medicines and pearlescent cosmetics), low-melting alloys, 

 and metallurgical additives. 



A continued supply of bismuth must come as a byproduct 

 from the major producers of lead, zinc, and copper in the 

 Western United States. Other potential sources in the United 

 States are molybdenum and tungsten ores, coal ash from 

 West Virginia coals, and oceanic manganese nodules. Bis- 

 muth is known to occur in lead deposits in the Appalachian 

 Mountains from North Carolina to Maine. Host rocks include 

 Precambrian dolomites west of the Adirondack Mountains 

 in New York and Precambrian and Cambrian schists east of 

 the Blue Ridge in North Carolina. Bismuth content of some 

 metamorphic rocks in the Piedmont province is relatively 

 high. Pegmatites in southeastern Pennsylvania and in west- 

 ern Maine commonly carry native bismuth and bismuthinite 

 in small amounts. 



Should lead production be curtailed by continued closings 



of smelters, especially those with bismuth recovery units, the 

 domestic supply of bismuth will be seriously affected; con- 

 sequently, research and exploration for bismuth-bearing 

 minerals should be continued. 



INTRODUCTION 



Bismuth is obtained largely as a byproduct from 

 ores of other metals, principally lead and copper. 

 Lesser amounts of bismuth are associated with mo- 

 lybdenum, cobalt, gold, silver, tin, tungsten, and 

 zinc. Despite its quantitative scarcity, the frequency 

 of occurrence of bismuth is remarkably high. The 

 bismuth minerals bismite (BioOs) and bismuthinite 

 (BisSa) are vs^idely distributed in small quantities in 

 ores throughout all the continents (Paone, 1970). 

 Bismuth reserves in the United States are dependent 

 on western U.S. lead reserves, which average about 

 7 pounds bismuth per ton of lead (0.35 percent), or 

 100 ppm (parts per million) bismuth in 3-percent 

 lead ore (R. L. Erickson, written commun., 1972). 



Free-world countries known to have major bis- 

 muth reserves are Japan, 95,200,000 pounds ; Mexico, 

 25 million pounds; and Peru, 20 million pounds. 

 Bolivia, Canada, South Korea, France, and Yugo- 

 slavia together have a reserve of about 18 million 

 pounds (U.S. Department of the Interior, 1972, p. 

 24-26). 



The principal uses for bismuth are in low-melting 

 alloys, in metallurgical additives for aluminum, car- 

 bon steel, and malleable iron, in pearlescent cos- 

 metic pigments, in medicines, and in a variety of 

 other smaller specialized applications. The largest 

 single use of bismuth continues to be in the phar- 

 maceutical field. 



Small quantities of bismuth compounds are used 

 as an accelerating agent in the rubber vulcanizing 

 process. A bismuth-cadmium alloy is used in the 

 production of some selenium rectifiers, and a few 

 thousand pounds of metal is consumed each year in 

 the manufacture of bismuth-tellurium electronic 



U.S. GEOL. SURVEY PROF. PAPER 820 



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