PHOSPHATE DEPOSITS 



521 



Table 105. — Phosphate resources of the United States 



[In metric tons of rocks containing more than 24 percent P2O5] 



Eastern United States 



Atlantic Coastal Plain: 



Florida (Polk, Hills- 

 borough). 



Florida (Manatee, Hardee, 

 DeSoto). 



North Florida-South 

 (Jeorgia. 



River pebble 



Hardrock 



North Gfeorgia 



South Carolina 



North Carolina 



Total Atlantic Coastal 

 Plain (rounded). 

 Tennesse, Kentucky, Alabama. 

 Others (Arkansas, Iowa) 



Total phosphate re- 

 sources. Eastern 

 United States. 



Total, tons of phosphorus 



Western United States 



Idaho, Montana, Utah, 6.0 X 10° 8.7 X 10" 



Wyoming (Phosphoria 



Formation). 



Utah (Mississippian rocks) 16 X 10° 



Alaska 1 X 10' 



Others (Nevada, California) __ 10° 



Total, phosphate re- 6.0 X 10° 9.7 X 10° 



sources. Western 



United States. 

 Total, tons of phosphorus. 0.78 X 10' 1.02 X 10° 



Grand total, tons 1.4 X 10° 2.7 X 10" 



of phosphorus. 



' Identified resources: Specific, identified mineral deposits that may or 

 may not be evaluated as to extent and grade, and whose contained 

 minerals may or may not be profitably recoverable with existing tech- 

 nology and economic conditions. 



-Hypothetical resources: Undiscovered mineral deposits, whether of 

 recoverable or subeconomic grade, that are geologically predictable as 

 existing in known districts. 



Table 106. — World phosphate resources 



[Metric tons of percent phosphorus] 



Identified Hypothetical 



resources ^ resources ^ 



United States 1.4 X 10° 2.7 X 10° 



Africa: Sedimentary 3.5 X 10° 6 X 10" 



Igneous 15 X 10° 15 X 10' 



Near East .13 X 10° .6 X 10° 



Latin America: Sedimentary 80 X 10° .2 X 10° 



Igneous 13 X 10" 10 X 10" 



Guano 5 X 10° Nil 



Asia: Sedimentary .2X10° .5X10" 



Igneous .2 X 10° .2 X 10° 



Australia .2 X 10' IX 10" 



Pacific Islands 6 X 10° 3 X 10" 



Total (rounded) 6 X 10" 9 X 10° 



^ Identified resources: Specific, identified mineral deposits that may or 

 may not be evaluated as to extent and grade, and whose contained min- 

 erals may or may not be profitably recoverable with existing technology 

 and economic conditions. 



2 Hypothetical resources; Undiscovered mineral deposits, whether of 

 recoverable or subeconomic grade, that are geologically predictable as 

 existing in known districts. 



amounts could be assigned. Additional hypothetical 

 resources are probably large. Although all these re- 

 sources are hypothetical, those not enumerated in 

 table 105 are of a lower order of precision in terms 

 of tonnage and are deeply buried, low in grade, or 

 contain deleterious gangue minerals, and as a result 

 they pose such different mining and processing 

 problems that it seems logical to discuss them sepa- 

 rately. 



The principal additional hypothetical resource for 

 the Western United States is contained in the 

 Phosphoria Formation. Extrapolation of average 

 thickness and phosphorus content over the entire 

 area underlain by the Phosphoria indicates a total 

 potential resource of about 16 X 10^ tons of P. Of 

 this amount, about 2 X 10" tons is represented by 

 the identified and hypothetical resources shown in 

 table 105. Subtracting this 2 X 10" tons from the 

 total potential of 16 X 10" tons leaves about 14 X 

 10" tons of P that may be considered to be an addi- 

 tional hypothetical resource in the Phosphoria For- 

 mation. Of this latter amount, 5 X 10" tons contains 

 more than 24 percent P2O5 ; 6 X 10" tons contains 

 from 10 to 23 percent P2O5, and the rest consists of 

 resources of low value. This resource will require 

 new mining and processing techniques. 



Additional hypothetical resources in the Eastern 

 United States can be divided into sandy phosphorite 

 of the Florida and North Carohna type and phos- 

 phatic carbonate rock such as the Hawthorn Forma- 

 tion of Florida. Phosphatic carbonate rock may con- 

 tain scores to hundreds of billions of tons of phos- 

 phate particles, and as much as 10 X 10" tons of P. 

 This material cannot be mined or processed with 

 present methods. 



Sandy phosphorite deposits of ths Atlantic 

 Coastal Plain are known from central Florida to 

 North Carolina, and additional undiscovered depos- 

 its may be present in the subsurface as far north 

 as Virginia. Deposits that are not known are com- 

 pletely and perhaps deeply buried; resources may 

 aggregate billions of tons of pellets and hundreds 

 of millions of tons of phosphorus. 



In northern Alaska, hundreds of square miles are 

 probably underlain by phosphorite, and the total 

 tonnage represented would be billions of tons of 

 rock that contain at least 10 percent P2O5, and thus, 

 hundreds of millions of tons of phosphorus. 



Large resources of phosphate rock exist offshore, 

 but close to the shoreline, in the Pacific Ocean from 

 southern California to southern Baja California and 

 in the Atlantic Ocean from North Carolina to 

 southern Florida. 



Phosphate is present as very coarse nodules in 



