STEEL ALLOY METALS
THERE is no strategic mineral of the United States for which an absolute insurance of supply in time of war is more essential than manganese. Although useful for certain chemical purposes and as a constituent of alloys requiring toughness and resistance to corrosion, its basic importance derives from the fact that it is indispensable to the manufacture of steel.1 Under existing metallurgical technique, manganese is the only agent which can be economically employed as a deoxidizer and desulphurizer in blast furnace operations. It is, in other words, the third element necessary in union with coal and iron for the production of steel. And inasmuch as steel is the basic material of modern mechanized warfare, the lack of an adequate supply of manganese during an extreme emergency would result in a serious handicap to both our essential industries and our defense organization. National security necessitates, therefore, that a guarantee of procurement of this vitally important strategic metal be assured in case of war.
There is a distinction which should be made, however, between the various grades of manganese-bearing ores, particularly as related to their specific uses. The first and most important is ferro-grade ore, which is relatively low in iron con-
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