100 • Marine Minerals: Exploring Our New Ocean Frontier 



the major foreign sources of supply are considered 

 to be secure, and there is little risk of supply inter- 

 ruptions. 



Domestic Resources and Reserves 



The U.S. reserve base is estimated to be about 

 53 million tons of zinc. Domestic reserves are nearly 

 22 million tons. Zinc is generally associated with 

 other minerals containing precious metals, lead, 

 and/or copper. The world reserve base is estimated 

 to be 300 million tons of zinc, with major deposits 

 located in Canada, Australia, Peru, and Mexico. 

 World zinc resources are estimated to be nearly 2 

 billion tons.''" Zinc occurs in seabed polymetallic 

 sulfide deposits along with numerous other metals. 

 The few samples of sulfide material that have been 

 recovered for anadysis show wide ranges in zinc con- 

 tent (30-0.2 percent). 61 



Domestic Production 



U.S. mine production of zinc in 1986 was about 

 209,000 tons, down from 485,000 tons in 1976. The 

 decline is attributed to poor market conditions and 

 depressed prices. Some mines shut down in 1986 

 are expected to reopen in 1987, and new mines will 

 open. Production is then expected to return to 

 around the 1985 level, or about 250,000 tons. Do- 

 mestic zinc metal production in 1986 also reached 

 lows comparable to those of the depression in the 

 early 1930s. Recycling accounted for 413,000 tons 

 of zinc — about 37 percent of domestic consump- 

 tion—in 1986. 



Future Demand and Technological Trends 



The U.S. Bureau of Mines forecasts that both 

 domestic and world zinc demand will increase at 



the rate of about 2 percent annually through 2000. 

 Probable U.S. demand in 2000 is forecast to be 

 about 1.5 mOlion tons, with possible demand rang- 

 ing between a low of 1 . 1 million tons and a high 

 of 2.3 milhon tons (table 3-9). 



A major determinant of future zinc demand wUl 

 be its use in the construction (galvinized metal 

 structural members) and automotive industries, 

 which together account for about 60 percent of zinc 

 consumption in the U.S. Although use of zinc by 

 the domestic automotive industry has decreased in 

 recent years, this trend is expected to reverse, and 

 manufacturers will again use more electro-galva- 

 nized, corrosion-resistant parts as a competitive 

 strategy through extended warranty protection. 



Aluminum, plastics, and magnesium can substi- 

 tute for many zinc uses, including castings, protec- 

 tive coatings, and corrosion protection. Aluminum, 

 magnesium, titanium, and zirconium compete with 

 zinc for some chemical and pigment applications. 



It is likely that the U.S. will continue to rely in 

 part on foreign sources of supply; however, domes- 

 tic resources in Alaska and perhaps Wisconsin 

 might be developed to offset some imports. ^^ Sec- 

 ondary sources and recycling of zinc could become 

 more important in the future with improvements 

 in recycling technology and better market con- 

 ditions. 



Gold 

 Properties and Uses 



Gold is a unique commodity because it is con- 

 sidered a measure and store of wealth. Jewelry and 

 art accounted for 48 percent of its use in the United 



'°J. Jolly, "Zinc," Mineral Commodity Summaries — 1987, p. 181. 

 "McKelvey, Subsea Mineral Resources, p. 82. 



"Jolly, "Zinc," Mineral Facts and Problems — 1985 Edition, Bulle- 

 tin 675 (Washington, DC: U.S. Bureau of Mines, 1986), p. 939. 



Table 3-9.— Forecast of U.S. and World Zinc Demand in 2000 



2000 



Actual Low Probable High 



(thousand tons) 



1,130^ 1,100 "1,540 2,310 



6,340 7,490 8,820 10,250 



— 8,590 10,36.0 12,560 



^U.S. data for 1986 from J. Jolly, "Zinc," M/nera/Commotf/fy Summaries— 1987 (Washington, DC: U.S. Bureau of IVIines, 1987), p. 180, world data for 1983 from source below. 

 SOURCE: Adapted from J. Jolly, "Zinc," Mineral Fads and Problems— 1985 Edition (Wasliington, DC: U.S. Bureau of Mines, 1986), p. 938. 



