60 



UNITED STATES MINERAL RESOURCES 



deposits, about 10 million tons should be a recover- 

 able resource. 



PROSPECTING TECHNIQUES 



Arsenic has not been and is not a sought-after 

 commodity; it is produced as a byproduct of other 

 commodities — gold, silver, or copper — and conse- 

 quently, no prospecting endeavor has been aimed 

 solely at finding it, although techniques suitable for 

 finding other commodities are well suited for find- 

 ing it. 



Some small arsenic deposits containing realgar or 

 arsenopyrite were no doubt found by recognition of 

 the ore minerals or their gossans in place, in float, 

 or in stream gravels. The Boliden arsenical copper 

 deposit in Sweden was found by an electrical geo- 

 physical method following the discovery of sulfide 

 boulders in till which blanketed the region. Arsenic 

 in soils and stream sediments may be detected by 

 geochemical methods and has been used as a guide 

 to other metals, including cobalt, tungsten, gold, 

 and silver; as such, it can be used as a guide to 

 arsenical metal deposits. Its mobility, however, is 

 restricted by the presence of high iron in soils and 

 stream sediments. 



PROBLEMS FOR RESEARCH 



Because arsenic historically has been sufficently 

 abundant to meet human needs and has been ob- 

 tained almost wholly as a byproduct of other com- 

 modities, it has not been intensively studied. The 

 ever-persistent problem of supply of most other 

 commodities will eventually include arsenic. Re- 

 search is needed so that the geologic relations of 

 arsenic can be better understood and guides can be 

 found for the discovery of new deposits. 



Much fundamental background knowledge on 

 arsenical deposits is needed. Arsenic minerals which 

 occur in many ore deposits are reported only in a 

 cursory manner, and only rarely are estimates of 

 their proportions to the associated metals given. 

 Also the relationship of arsenic to primary or host 

 commodities needs additional study. Arsenic occurs 

 randomly with several metals including gold, cop- 

 per, and tin, but its occurrence with these metals 

 is not fully understood. Further study might make 

 possible more accurate predictions of the occurrence 

 of arsenic with these metals on a districtwide or 

 regionwide scale. 



SELECTED REFERENCES 



Ahlfeld, Frederick, 1931, The tin ores of Uncia-Lallagua, 



Bolivia: Econ. Geology, v. 16, no. 3, p. 241-257. 

 Anderson, C. A., 1969, Massive sulfide deposits and vol- 



canlsm: Econ. Geology, v. 64, no. 42, p. 129-146. 

 Anderson, C. A., and Creasey, S. C, 1958, Geology and ore 

 deposits of the Jerome area, Yavapai County, Arizona: 

 U.S- Geol. Survey Prof. Paper 308, 185 p. 

 Berg, H. C, and Cobb, E. H., 1967, Metalliferous lode de- 

 posits of Alaska: U.S. Geol. Survey Bull. 1246, 254 p. 

 Brown, Randall, and Waters, A. C, 1951, Quicksilver de- 

 posits of the Bonanza-Nonpareil district, Douglas 

 County, Oregon: U.S. Geol. Survey Bull. 955-F, p. 225- 

 251- 

 Burbank, W. S., Matthews, A. F., and Mosier, McHenry, 

 1947, Arsenic, in Hearings before a subcommittee of 

 the committee on public lands: U.S. Senate, 80th Cong., 

 1st sess., p. 214-216. 

 Butler, B. S., Loughlin, G. F., Heikes, V. C, and others, 

 1920, The ore deposits of Utah: US. Geol. Survey Prof. 

 Paper 111, 672 p. 

 Connolly, H. J. C, 1953, The Aberfoyle tin-wolfram mine, 

 in Geology of Australian ore deposits: Empire Mining 

 and Metall. Cong., Australia and New Zealand, 5th, 

 Melbourne 1953, v. 1, p. 1200-1208. 

 Ferguson, E. H., and Bateman, A. H., 1912, Geologic fea- 

 tures of tin deposits: Econ. Geology, v. 7, no. 3, p- 

 209-262. 

 Forman, F. G., 1953, Geological structure of the shield in 

 southern Western Australia in relation to mineraliza- 

 tion, in Geology of Australian ore deposits : Empire Min- 

 ing and Metall. Cong., Australia and New Zealand, 5th, 

 Melbourne 1953, v. 1, p. 65-77. 

 Gair, J. E., 1962, Geology and ore deposits of the Nova Lima 

 and Rio Acima quadrangles, Minas Gerais, Brazil: U.S. 

 Geol. Survey Prof- Paper 341-A, 67 p. 

 Graton, L. C, Burrell, H. C, and others, 1935, The Morococha 

 district, 1935, in Copper resources of the world, v. 2 : 

 Internat. Geol. Cong., 16th, Washington, D.C. 1933, p. 

 527-544. 

 Grip, Erland, 1960, The Skellefte district and Laisvall area, 

 in Grip, Erland, Quensel, Percy, Geijer, Per, and 

 Ljunggren, Sven, Sulphide and iron ores of Vaster- 

 botten and Lapland, northern Sweden : Internat. Geol- 

 Cong., 21st, Copenhagen 1960, Guide to excursions A27 

 and C22, p. 3-14. 

 Grip, Erland, and Wirstam, A., 1970, The Boliden sulfide 

 deposit — A review of geo-investigations carried out 

 during the lifetime of the Boliden mine, Sweden, 1924- 

 1967: Sveriges Geol. Undersokning, Arsbok, v. 64, no. 

 8, 68 p. 

 Hewitt, W. P., 1968, Western Utah, eastern and central 

 Nevada, in Ore deposits of the United States, 1933- 

 1967: Am. Inst. Mining, Metall., and Petroleum Engi- 

 neers, V. 1, p- 857-885. 

 Kanehara, Nobuyasu, 1935, Copper resources of Japan, in 

 Copper resources of the world, v. 2 : Internat. Geol. 

 Cong., 16th, Washington, D.C. 1933, p. 687-700. 

 Kinkel, A. R., Jr., Santos- Yiiigo, L. M., Samaniego, Sisen- 

 audo, and Crispin, Oscar, 1956, Geology of Lepanto 

 copper mine, in Copper deposits of the Philippines, pt- 

 1 : Philippines Bur. Mines, p. 17-50. 

 Krauskopf, K. B., 1955, Sedimentary deposits of rare metals, 

 in Pt. 1 of Bateman, A. M. ed., Economic geology, 50th 

 anniversary volume, 1905-1955: Econ. Geology Pub. 

 Co., p. 411-463. 

 Lang, A. H., Goodwin, A. M., Mulligan, R., Whitmore, D. 

 R. E., Gross, G. A., Boyle, R. W., Johnston, A. G., 



