646 



UNITED STATES MINERAL RESOURCES 



Table 135. — Ti7i reserves and resources of the world, in long tons of tin metal 



Reserves: Identified deposits from which minerals can be extracted 

 profitably with existing technology and under present economic con- 

 ditions. 



Conditional resoiu-ces: Specific, identified mineral deposits whose con- 

 tained minerals are not profitably recoverable with existinsr tech- 

 nology and economic conditions. 



North America: 

 U.S.A. — 



Canada 



Mexico 



Total 



South America: 



Bolivia 



Brazil 



Argentina 



Total 



Europe : 



England 



Spain and Portugal 

 France 



Total 



Asia, Non-Communist: 



Indonesia ' 



Malaysia 



Thailand = 



Burma 



Other countries __ 



Total 



Africa: 



Nigeria 



Zaire 



Other countries ' _ 



Total 



Australia and Tasmania 



China'" 



U.S.S.R.^ 



Hypothetical resources: Undiscovered mineral deposits, whether of re- 

 coverable or subeconomic grade, that are geologically predictable as 

 existing in known districts. 



Speculative resources: Undiscovered mineral deposits, whether of recover- 

 able or subeconomic grade, that may exist in unknown districts or in 

 unrecognized or unconventional form. 



500,000 

 600,000 

 217,000 

 250,000 

 17,500 



World total 3,649,965 



14,000 



43,000 

 14,000 



40,000 



1,860,000 

 230,000 



1,000,000 



250,000 



90,000 



540,000 

 ii8'60,000 



6,327,800 



5,888,000 



4,373,000 



9,289,000 



70,000 



200,000 



47,700 



540,000 



1,000,000 1,500,000 1,000,000 



1,500,000 1,000,000 



250,000 250,000 



100,000 



7,504,700 



' Inferred reserves in Indonesia are greatly expanded over the estimate 

 of Sainsbury (1909) on the basis of grade of placer deposits being 

 dredged currently in Malaysia and Indonesia. Present grade of Indonesia 

 dredge ground is about 0.62 lbs per cu yd, somewhat higher than that 

 dredged in Malaysia in 1947. Hence, before grade in Indonesian placers 

 falls to the level of current grades in Malaysia, as much tin will be 

 produced from Indonesian placers as was produced in Malaysia between 

 1937 and 1971, or about 1,860,000 long tons. 



applied for Thailand 

 ere equal to those of 



2 The same computation used for Indonesia 

 on the assumption that the stanniferous are 

 Malaysia. 



■' In old channels buried under volcanic rocks. 



* Republic of South Africa, South West Africa, Southern Rhodesia, 

 Cameroons, Burundi-Urundi, and the north African countries. 



^ These are classed as no better than educated guesses. 



SPECULATIVE RESOURCES 



In assessing the possibility of finding new dis- 

 tricts, several factors unique to tin must be con- 

 sidered. These are: 



1. Tin has been mined and used throughout the 



world for thousands of years, and whatever 

 major tin deposits exist in regions settled or 

 penetrated by civilized peoples have probably 

 been discovered. Conversely, entire new dis- 

 tricts might still be found in remoter regions, 

 as attested by the recent discovery of a major 

 district (Rondonia) in western Brazil. 



2. Each discovery of new tin deposits merely rein- 



forces the fact that deposits containing eco- 



nomic amounts of tin are invariably similar to 

 those deposits which have been mined for 

 thousands of years. One cannot, therefore, even 

 validly speculate that new types of deposits 

 will be found for tin, such as have been found 

 recently for beryllium (Spor Mountain, Utah; 

 Lost River, Alaska) or for gold (Carlin and 

 Cortez, Nev.). 

 Many of the great mining districts of the world 

 were found by Cornish miners who left Corn- 

 wall after her mining industry collapsed, and 

 who migrated all over the world. In their 

 search for gold, diamonds, or base metals, these 

 miners are unlikely to have overlooked major 



