18. What commercial procjucts other than fish are obtained 

 from the sea? 



Products obtained commercially from sea water include common 

 salt, bromine, and magnesium. All of the United States' supply of mag- 

 nesium is taken from sea water, because extraction is cheaper than ob- 

 taining it from mines on land. About 75 percent of our supply of bro- 

 mine is extracted from the sea. 



In recent years interest has developed in exploiting the seemingly 

 inexhaustible supply of manganese and phosphate-rich nodules on the 

 sea floor. The American Institute of Mining, Metallurgical, and Petro- 

 leum Engineers (AIME) has estimated that there are 1.5 trillion tons of 

 manganese nodules on the bottom of the Pacific Ocean. These nodules 

 contain as much as 50 percent manganese plus smaller amounts of 

 nickel, copper, cobalt, and other metals. Nodules on the sea floor appear 

 to be forming faster than the rate at which the United States is now 

 using manganese, nickel, and cobalt; thus it seems that our reserve of 

 these metals is assured for many years. Phosphorite nodules off the 

 California coast could satisfy California's phosphate fertilizer needs for 

 many years. 



Other materials obtained from the sea floor or beaches include dia- 

 monds, pearls, sand, gravel, shell, and ores of tin, thorium, and titanium. 



Oil is being recovered from beneath the ocean floor in increasing 

 amounts. In 1960, about 8 percent of the free world's oil supply was 

 obtained from this source; by 1965, it had increased to 16 percent. 

 Undersea deposits of sulfur are also being tapped by drilling from plat- 

 forms in the Gulf of Mexico, as the supply on land dwindles. 



Carson, R. L. 



The Sea Around Us, Oxford University Press, 1951; Mentor Books, 



(Paperback), 1954. 

 Stewart, Harris B., Jr. 



Deep Challenge, Van Nostrand, 1966. 

 U. S. Bureau of Mines 



Mineral Yearbook, 1963, Washington, D. C, 1964. 



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