taken by the International Tin Council. However, a slow, long-term rise in prices to the range of $1.50 to 

 $2.00 per pound can be expected. The average annual U.S. growth rate in tin consumption from 1966 to 

 1980 is expected to be about 1 per cent. Virtually all of the U.S. supply of primary tin will be obtained 

 from imports. 



Possible substitute materials. In the largest use of tin-as tinplate for cans-there are numerous 

 alternate materials, including glass, paper, plastics, and aluminum. Nonmetallic materials, copper, 

 aluminum, and zinc-coated products, have largely replaced tinplate and terneplate for roofing and 

 construction. Silver or antimony may be used in solder in place of tin. In other alloys, low-tin bronze 

 and roller or ball-bearings may be substituted for babbitt metal containing tin. Wrapping material such as 

 aluminum, plastics, or paper may replace tinfoil. Other chemical compounds may replace tin compounds 

 for use as fungicides and insecticides, slime-control reagents, and an enamel opacifier in ceramics. 



Potential from marine sources.'*^ The United States has no known primary tin deposits of economic 

 grade or size. Primary tin deposits are associated with granitic rocks which generally are known to be 

 present in only a few places in the U.S. continental shelves. 



Cassiterite, the only commercial tin mineral, is readily concentrated in placers; large and rich tin 

 placers are being exploited in several areas of the world. The only tin placers of significant size in the 

 United States are on the western tip of the Seward Peninsula;^ ° these are being worked by four to eight 

 men during the summer months. Total production is unknown but probably is less than $200,000 

 annually. Reserves are estimated to be 3,000 tons, worth perhaps $6-8 million. However the deposits 

 are in small pockets, difficult to work, thus deterring the development of large production facilities. No 

 offshore sampUng has yet been done but a small low grade cassiterite deposit totaling perhaps 1000 tons 

 may be inferred off the Seward Peninsula. No other tin deposits are likely on the U.S. continental 

 shelves or on the shelves of Hawaii, Puerto Rico, or the Virgin Islands. 



TITANIUM 



Uses. More than 95 per cent of titanium is used as titanium dioxide in pigments. Titanium is also used 

 as a metal, as welding rod coatings, for non-titanium-base alloys and carbide, and for ceramics, fiber 

 glass, and chemicals. Its use as a structural metal is increasing, particularly in the aerospace industry, 

 where its high strength-to-weight ratio holds an advantage over aluminum and stainless steel. Titanium is 

 not a rare element, being the ninth most abundant in the continental crust. 



Prospective supplies and prices. The titanium resource is in the form of two minerals: Umenite and 

 rutile. Ilmenite is eminently suitable and widely used as a source for titanium dioxide used in pigments. 

 Rutile however is preferred over ilmenite as the raw material for titanium metal because of metallurgical 

 factors. Both the United States and the world have large land-based resources of ilmenite. Australia and 

 Sierra Leone are the chief sources of rutile. 



The trend in the price of primary titanium (sponge metal) has been continually downward since the 

 metal was first produced commercially in 1948. Commercial titanium sponge sold for about $5.00 per 

 pound in 1948 and by the end of 1963 was selling for $1.27 to $1.60 per pound. Owing to abundant 

 supplies of titanium raw materials and a high relative use of electric power (which shows a downward 

 price trend) it is likely that the price of titanium will continue to decline although more slowly than in 

 recent years. 



Possible substitute materials. Selection of titanium metal over other materials of construction is 

 normally made on a performance versus economic basis. High-strength steels, aluminum, or other metals 

 may be substituted for titanium in many structural applications but such substitution usually 

 necessitates redesign and results in lower performance. In applications where titanium's corrosion 



Summarized largely from Ocean Science and Engineering, Inc. report. 



so 



J. E. Shelton, "Tin," in Mineral Facts and Problems, Bureau of Mines Bull. No. 630, 1965. 



VII-159 



