22 



UNITED STATES MINERAL RESOURCES 



elements in the United States at that time was 

 roughly equal to their crustal abundance times 1 

 billion or times 10 billion. 



I realize that abundance figures for some of the 

 elements are still unproved, that reserve figures are 

 alvi^ays questionable, and that the assumption of 

 log-normal distribution of trace elements in the 

 earth's crust is not universally accepted. However, 

 even rather large changes in abundance or reserve 

 estimates will not affect the concepts discussed here. 



Table 3 combines the abundance data of Lee and 

 Yao and the reserve-abundance relationship of Mc- 

 Kelvey with my own attempt at calculating the total 

 amounts of several metals in the earth's crust, vari- 

 ous segments of the crust. United States crust, 

 United States crust to a 1-kilometer depth, and po- 

 tential resources of recoverable ores. 



Study of the table permits speculation about 

 the position of the United States and the world with 

 respect to mineral resources. For example, one could 



consider the total amount of an element present in 

 the United States crust to a 1-kilometer depth as the 

 ultimate United States resource of that element and 

 portion it out by mineralogy or rock type. If an ele- 

 ment tends to be lithophile, and thus occurs chiefly 

 in silicate minerals, then a high percentage is prob- 

 ably forever unavailable as a resource. If an element 

 is sulfophile, probably a greater amount is available 

 as a resource. Or one might estimate, by working 

 portion it out by mineralogy or rock type. If an ele- 

 ment present at various grade levels in the United 

 States crust to a 1-kilometer depth. 



Table 3 shows that the most commonly sought 

 metals, except lead, are more abundant in oceanic 

 crust than in continental crust. This permits the 

 speculation that perhaps we should make resource 

 target maps showing the areas of the world where 

 segments of oceanic crust are within reasonable ex- 

 ploration depths. 



The part of the table showing resource potential 



Table 3. — Abundance, mass, reserves, and resources of soms 



[Abundance in grams/metric ton (g/mt); maas and reserves in metric tons (mt). 



Continental 

 crust segments 



TotaJ earth's crust 



Oceanic crust 



Continental crust 



Element Gold- Vino- Lee and 



Schmidt ' gradov ' Yao ' 

 (g/mt) (g/mt) (g/mt) 



Antimony 1 o.B 62 



Beryllium 6 3.8 1.3 



Bismuth .2 .009 .0043 



Cobalt 40 18 2B, 



Copper 70 47 63 



Gold .001 .0043 .0035 



Lead 16 16 12 



Lithium 66 32 21 



Mercury .5 .083 .089 



Molybdenum 2.3 1.1 1.3 



Nickel 100 B8 89 



Niobium 20 21 19 



Platinum .005 .046 



Selenium .09 .06 .075 



Silver .02 .07 .076 



Tantalum 2.1 2.5 1.6 



Tellurium .0018 .001 .00065 



Thorium 11.5 13 6.8 



Tin 40 2.5 1.7 



Tungsten 1 1.3 1.1 



Uranium 4 2.5 1.7 



Zinc 80 83 94 



G/mt G/mt G/mt 



Aluminum 81,300 80,600 83,000 



Barium 430 660 390 



Chromium 200 83 110 



Fluorine goo 660 450 



Iron 50,000 46,500 68,000 



Manganese 1,000 1,100 1,300 



Phosphorus 1,200 930 1,200 



Titanium 4,400 4,500 6,400 



Vanadium IBO 91 140 



'G/mt MtXlO' 



14.6 

 1,200 

 160 



1.8 

 38.4 



.013 

 140 

 40.8 

 26.4 

 40.8 

 2,250 



0.46 

 1.5 

 .0029 



.028 

 .059 

 .065 



16.6 

 920 

 300 



18.1 

 33 

 1,220 



.031 

 .064 

 .067 



11.6 

 .680 

 210 



16.3 

 12.7 

 22.6 

 870 



G/mt 



9.4 

 2.6 

 10.8 

 1,392 

 31,2 

 28.8 

 153.6 

 3.36 



84,000 



370 



160 



420 



76,000 



1,800 



1,400 



12.5 



72.1 



1.61 



77 



470 



48,000 



1,000 



1,200 



5,300 



120 



15.2 

 16.3 

 81.6 



81 



470 



49,000 



1,100 



1,200 



6,500 



120 



508 

 10.6 

 11.4 



67.1 



' U.S. Bureau Mines (1970); 1 short ton =0.91 mt. 



2 Recoverable resource potential = 2.46 A X 10 » (abundance A expressed in g/mt). 



= U.S. Bureau Mines (1970): 1 short ton =0.91 mt: does not include United States reserve. 



'Recoverable resource potential =2.45 A X17.3X10 ° (abundance A expressed in g/mt: land area of world ■ 



U.S. Bureau Mines (1970): data on world basis. 

 'Goldschmidt (1954, p. 74-75). 

 'Vinogradov (1962, p. 649-660). 



'Lee and Yao (1970, p. 778-786). All calculations are based on this work. 

 " Very high. 



17.3 times United States land area). 



