ALUMINUM AND BAUXITE 



39 



and Australia that seem favorable for discovery of 

 major new deposits of metallurgical-grade bauxite. 



Reserves of bauxite for abrasives, refractories, 

 and chemicals in the United States are approxi- 

 mately 5 million tons, and potential resources are 

 about 25 million tons. These deposits are in Arkan- 

 sas (Gordon and others, 1958) and in many small 

 districts scattered throughout the Appalachian re- 

 gion and the Coastal Plain in Southeastern United 

 States (Overstreet, 1964). Chemical-grade bauxite 

 is mined in Arkansas ; Andersonville, Ga. ; and the 

 northvi^est Georgia districts. Refractory-grade baux- 

 ite is mined in Arkansas and in the districts at 

 Eufaula, Ala., and Andersonville, Ga. Small quanti- 

 ties of refractory-grade bauxite are occasionally 

 mined where lenses of bauxite are found during 

 mining of kaolin in the extensive kaolin belt of 

 Georgia. Much of the refractory-grade bauxite pro- 

 duced domestically is used for mullite-type refrac- 

 tory products because of its high silica content, and 

 demand for such material is increasing. Abrasive- 

 grade bauxite has been produced in the Arkansas 

 district, but now most of it is imported in calcined 

 form from Guyana and Surinam. 



Guyana and Surinam are now the principal 

 sources of high-grade refractory bauxite for most 

 of the world. During the period of 1966-70, the 

 United States imported yearly from 145,000 to 

 237,000 long tons of bauxite, mainly for uses other 

 than metal, from Guyana (Kurtz, 1971, p. 6) and 

 from 16,000 to 48,000 long tons from Surinam. 

 Some calcined abrasive-grade bauxite has been re- 

 cently imported from the Weipa district in Aus- 

 tralia, and calcined bauxite is reported to be avail- 

 able in the Republic of Guinea; however, the long- 

 range potential of these sources is not yet clear. 



In the United States, possibilities remain for 

 finding additional small deposits of bauxite for re- 

 fractory and chemical uses in Arkansas and the 

 Southeastern States. Such deposits are likely to be 

 high in silica, and some will be deeply buried, but 

 the search for these hypothetical deposits may be- 

 come more profitable as domestic supplies diminish. 

 Suggested areas for exploration are (1) beneath 

 considerable cover downdip from the nepheline 

 syenite body on which the Arkansas deposits were 

 formed (Jespersen, 1964), and (2) in scattered 

 areas in the southern Appalachian region, where 

 sinkholes are abundant. 



OTHER POTENTIAL RESOURCES OF ALUMINUM 



Potential resources of aluminum other than baux- 

 ite comprise a variety of rocks and minerals, includ- 

 ing alunite, aluminous shale and slate, aluminum 



phosphate rock, dawsonite, high-alumina clays, 

 nepheline syenite, anorthosite, saprolite, coal ash, 

 and aluminum-bearing copper-leach solutions. Alu- 

 nite and nepheline syenite are being mined today in 

 the U.S.S.R. for alumina and other products. Else- 

 where in the world several of these resources have 

 been investigated in considerable detail, but they 

 are not mined because bauxite is available. The po- 

 tential aluminum resources in the United States 

 collectively amount to many billions of tons and are 

 virtually inexhaustible. Their use will depend largely 

 on costs of imported bauxite, alumina, and aluminum 

 and on advances in technology that will make them 

 competitive with imports. The United States could 

 become self-sufficient in aluminum now if a profit 

 in its production were not required. 



Alunite, KAl3(SO.,)2(OH)6, a white mineral con- 

 taining 37 percent alumina, commonly occurs in 

 veins, replacement bodies, and in disseminated form 

 in altered volcanic rocks. The mineral has potential 

 value for potash and sulfur as well as aluminum. 

 Alunite is a present source of aluminum in the 

 U.S.S.R., and an alunite processing plant is re- 

 portedly under construction in Mexico. In the United 

 States, alunite was investigated through the pilot- 

 plant stage as an emergency source of aluminum 

 during World War II. 



Recently, alunite deposits near Cedar City, Beaver 

 County, Utah, were explored by two companies 

 (Engineering and Mining Journal, 1971). The de- 

 posits are on lands under Federal potash permits in 

 the Wah Wah Mountains. Four zones of alunitized 

 Tertiary volcanic rocks, each more than 100 million 

 tons of rock, have been reportedly found by exten- 

 sive drilling. The deposits are said to be 35-45 

 percent alunite, and the remainder is mostly quartz. 

 Aluminum sulfate or alumina and potassium sulfate 

 are the proposed products from this deposit (W. W. 

 Walker, oral commun.. May 1972). If this initial 

 report on the size and grade of these deposits is 

 confirmed, they are a large potential resource of 

 aluminum, but whether or not this metal can be re- 

 covered profitably is yet to be determined. 



ALUMINUM PHOSPHATE ROCK 



The leached zone, 2-20 feet thick, occurring above 

 and stripped off in mining of phosphate deposits in 

 Florida, contains several aluminum phosphate min- 

 erals and minor quantities of uranium. The alumina 

 content of this rock ranges from 4 to 20 percent, 

 and the UsOs content from 0.005 to 0.02 percent. 

 These deposits in Florida extend over several hun- 



