Iron ore is traded duty-free in the markets of the non-Communist world. SuppUes of high grade iron 

 ore in international trade exceed demand and prices in general depend on negotiated contracts. Recent 

 quotations have been as low as $4 per ton for fines containing 60.5 per cent iron in Oregon and Alaska. 

 However, because of the greater distance of offshore deposits from source rocks the deposits will 

 probably be lower grade and smaller than onshore magnetite sand deposits. In general the outlook is very 

 poor for the recovery of magnetite from offshore placers during the remainder of the 20th century. 



Manganese nodules contain upwards of 1 2 per cent iron but if they are mined the iron might have to 

 be discarded because of metal separation problems. 



Bedrock deposits of iron ore do not occur in coastal areas of the conterminous United States, so the 

 prospects for finding such deposits in the continental shelves must be regarded as very poor. In Alaska, 

 large low grade iron deposits are known in the vicinity of Iliamna Lake near Cook Inlet. These may 

 extend offshore. Low grade titaniferous magnetite deposits that extend offshore are known about 30 

 miles southeast of Juneau. 



Hot brines from which iron oxide as well as other metals are precipitating have been found in the 

 deeps of the Red Sea* ' and iron precipitates have been identified from a submarine volcano in 

 Indonesia.*^ No hot spring or volcanic activity that might have given rise to these types of deposits are 

 known around the continental United States or Alaska. However, deposits from ancient volcanos active 

 during Tertiary or Mesozoic times might possibly be sandwiched in with sedimentary rocks in the 

 shelves. The Hawaiian Islands are of volcanic origin but no precipitates of this type have been identified 

 on land there and it is therefore unlikely that they will be found in the shelves. 



KYANITE AND SILUMANITE*^ 



The high alumina minerals kyanite and sillimanite (A 128105) are commonly present in Pleistocene 

 and recent placer deposits on the Atlantic coast from New Jersey south to the tip of Florida. Tailings 

 from the separation of titanium minerals and zircon from placer concentrates are enriched in kyanite 

 and sillimanite where these minerals are present in the raw sand. Procedures have been developed for the 

 preparation of a 90 to 95 per cent kyanite-siUimanite product from tailings at Florida placers. Resources 

 in onshore placers in Florida are estimated at about four million tons, and the offshore potential is 

 probably considerably less. 



MAGNESIUM 



Uses. Magnesium is the eighth most abundant element in the earth's crust and the second most 

 abundant element after sodium in sea water. Magnesium metal is used as a structural metal, as an 

 alloying constituent for other metals, and as a reducing agent to produce titanium, zirconium, hafnium, 

 uranium, and beryllium. Since 1956 the metallurgical uses for primary magnesium have exceeded the 

 structural uses, and in 1964 amounted to about 62 per cent of the total use figure. Magnesium as an 

 aluminum alloy accounts for two-thirds of this metallurgical classification. 



A wide variety of magnesium compounds are used in the chemical and pharmaceutical industries, and 

 magnesia (magnesium oxide) is used in substantial quantities as a refractory and in the cement, paper 

 pulp, rayon, fertilizer, insulation, and chemical industries. Only magnesium metal is included in the 

 following projections. 



A. K. Miller et ah, "Hot Brines and Recent Iron Deposits in Deeps of the Red Sea," Geochimica et Cosmochimica 

 Acta, Vol. 30, pp. 341-359, 1966. 

 1 2 

 K. K. Zelenov, "O Vozmozhnon Vulkanogennom Istochnike Veschestva Geosink Linalnykh, " in Symposium sur 

 les Bauxites (Zagreb, October 1963), Vol. 1, pp. 115-133, 1964. 



W. E. Overstreet, in V. E. McKelvey et al, "Potential Mineral Resources of the United States Outer Continental 

 Shelves," unpublished report of the Geological Survey to the PubUc Land Law Review Commission, March 1968. 



VII-138 



