88 • Marine Minerals: Exploring Our New Ocean Frontier 



rived from minerals known to occur within the U.S. 

 EEZ are included in the stockpile: rutile, platinum- 

 group metals, chromium, lead, manganese, nickel, 

 cobalt, zinc, chromium, copper, and titanium (ta- 

 ble 3-1). 



The stockpile program can affect minerals mar- 

 kets when there are large purchases to meet stock- 

 pile goals or sales of materials in excess of goals, 

 although the authorizing legislation prohibits trans- 

 actions that would disrupt normal marketing prac- 

 tices. Stockpile policies have on occasion opened 

 additional markets for certain minerals, while at 

 other times sales from the stockpile have signifi- 

 candy depressed some commodity prices. The mere 

 existence of stockpile inventories can also have a 

 psychological effect on potential mineral produc- 

 ers' actions. 



Table 3-1.— Major U.S. Strategic Materials 

 Contained in the National Defense Stockpile 



SOURCE: Adapted from Federal Emergency Management Agency, Stockpile 

 Report to the Congress (Washington, DC; Federal Emergency 

 Management Agency, 1986), pp. 30-31. 



SUBSTITUTION, CONSERVATION, AND RECYCLING 



Changes in production technology can substan- 

 tially affect minerals and materials use. Changes 

 in use are generally made in response to economic 

 incentives, although environmental regulations also 

 have been instrumental in promoting some conser- 

 vation and recycling. Cheaper materials or mate- 

 rials that perform better can replace their compet- 

 itors by substitution. Similarly, there is significant 

 motivation to reduce the amount of material used 

 in a production process or to use it more efficiently. 

 Finally, if the material is valuable enough to offset 

 the cost of collecting, separating, and reclaiming 

 scrap, there is an incentive to recycle the material 

 through secondary processing. Each of these op- 

 tions can reduce the demand for primary minerals 

 production. 



Materials substitution is a continuing, evolution- 

 ary process where one material displaces another 

 in a specific use. Examples of substitution abound. 

 Steel has replaced wood for floor joists, studs, and 

 siding in many construction applications. Plastics 

 are replacing wood as furniture parts and finishes, 

 many metals in non-stress applications, and steel 

 in automobile bodies. Ceramics show promise for 

 displacing carbide steels in some cutting tools and 

 some internal combustion engine components. 

 Glass fiber optics have replaced copper wire in some 



telecommunications applications. At a more ele- 

 mental level, there are other examples: manganese 

 can partially substitute for nickel and chromium 

 in some stainless steels; the increased use of nickel- 

 based superalloys have reduced the quantity of co- 

 balt used in aircraft engines; and, for some elec- 

 tronic applications, gold can replace platinum. 



Conservation technologies can reduce the 

 amount of metal used in the manufacturing proc- 

 ess. Near- net-shaping, in which metals are cast into 

 shapes that correspond closely to the final shape of 

 the object, can reduce materials waste in some in- 

 stances. Conventional processing generally involves 

 considerable machining of billets, bars, or other 

 standard precast shapes and generates substantial 

 amounts of mill cuttings and machine scrap. In 

 some cases, the ratio between purchased metal and 

 used metal may be as high as 10 to 1 .'^ While much 

 of this "new scrap" is reclaimed, some is contami- 

 nated and is unusable for high-performance appli- 

 cations like aircraft engines. 



Improvements in production processes can also 

 reduce metals needs. The use of manganese to 

 desulfurize steel has been reduced with the intro- 



"Office of Technology Assessment, Strategic Materials: Technol- 

 ogies to Reduce U.S. Import Vulnerability, p. 24. 



