A Text-Book of Elementary Metallurgy for the Use of Students #230676

Most metals in their natural state differ widely from their condition after subjection to the various smelting and refining operations by which they are separated from other matters associated with them in the earth. Ores of metals occur in two ways, viz., in the metallic state, the metal being free or simply mixed with other metals and in a state of chemical combination, which is by far the more common.