108 



UNITED STATES MINERAL RESOURCES 



Table 21. — Cadmium content, in percent, of sphalerite from selected U.S. and Canadian mining districts and regions 



Location 



Balmat-Edwards, N.Y 13 



Edwards, N.Y 1 



Franklin, N. J 1 



Friedensville, Pa 1 



Do 1 



Birmingham, Pa 3 



Valzinco, Va 1 



Timberville, Va 2 



Do 2 



Austinville, Va 12 



Austinville (and other occurrences in 11 



Cambrian rocks of southeastern U.S.). 



East Tennessee, Kingsport ores 6 



Do 6 



Ducktown, Tenn 1 



Middle Tennessee veins 6 



Middle Kentucky veins 37 



Illinois-Kentucky fluorspar district 5 



Upper Mississippi Valley 6 



Tri-State 15 



Oilman, Colo 1 



Rocky Mountain region (U.S. except Butte) 8 



Do 5 



Butte, Mont 3 



Do 3 



Coeur d'Alene, Idaho 59 



Metaline, Wash 2 



Northport, Wash 3 



Western Canada, chiefly British Columbia 118 



Ontario and Quebec 5 



Pine Point, Northwest Territories 4 



^ Composite. 

 ■ Not given. 



Average 



Lenker, 1962. 



Warren and Thompson, 1945. 



Lenker, 1962. 



Callahan, 1968. 



Warren and Thompson, 1945. 



Lenker, 1962. 



Maher and Pagan, 1970. 



Lenker, 1962. 



Maher and Pagan, 1970. 



Lenker, 1962. 



Maher and Pagan, 1970. 



Lenker, 1962. 



Maher and Pagan, 1970. 



Do. 

 Jolly and Heyl, 1968. 



Do. 

 Hall and Heyl, 1968. 



Do. 

 Siebenthal, 1909. 

 Lenker, 1962. 

 Kaiser and others, 1954. 

 Warren and Thompson, 1945. 

 Kaiser and others, 1954. 

 Warren and Thompson, 1945. 

 Pryklund and Fletcher, 1956. 

 Kaiser and others, 1954. 



Do. 

 Warren and Thompson, 1945. 



Do. 

 Evans and others, 1968. 



Table 22. — Estimated identified and undiscovered cadmium, 

 resources of the United States and the world 



[Values given are in thousands of metric tons of contained cadmium] 



Undis- 

 Identified covered Total 



resources resources resources 



United States 



Recoverable 295 400 695 



Subeconomic 1,500 



Total ___ ___ 2,195 



Rest of the world 



Recoverable 950 1,425 2,375 



Subeconomic 14,000 



Total _.. ___ 16,375 



Total world 



Recoverable 1,245 1,825 3,070 



Subeconomic 15,500 



Total _.. _.. 18,570 



applying Zn:Cd ratios of various geologic materials 

 (such as those in table 20) to the basic data from 

 which zinc resources were estimated. (See "Zinc," 

 this volume.) The proximity of the estimate of re- 

 coverable cadmium resources in the United States 

 (695,000 mt, in table 22) to the reserve potential 

 (860,000 mt) suggests that the United States may be 



nearing its potential for cadmium associated with 

 zinc ores as currently mined. On the other hand, the 

 potential subeconomic resources, both identified and 

 undiscovered, imply that there is no significant possi- 

 ble long-range shortage of cadmium from U.S. 

 sources. The data in table 22 also indicate that world 

 resources of cadmium, estimated at more than 18 

 million mt, are probably more than adequate for fu- 

 ture needs as currently projected. One likely source 

 for the future may well be marine phosphorites from 

 which both zinc and cadmium could be extracted dur- 

 ing the preparation of superphosphate fertilizers, al- 

 though small amounts of these elements are un- 

 doubtedly needed in the final fertilizer product as 

 trace nutrients. 



Table 23 shows the distribution of recoverable 

 identified cadmium resources of the United States by 

 major geologic regions and compares these estimates 

 with those for zinc in the same regions. Also given 

 are the approximate Zn:Cd ratios for the respective 

 zinc and cadmium recoverable identified resources of 

 these regions. The Zn:Cd ratio of 150 for the total of 

 these U.S. resources indicates that the greater part 

 of this country's zinc ores are in mineral deposits 

 that contain relatively more cadmium than the esti- 

 mated world average (Zn:Cd ratio 230, table 20). 



