Some metals are so critical to the US economy the the Federal Government retains a strategic stock pile of them. This program describes how these metals are produced and what they are used for that make them so valuable: copper, iron, lead...See moreSome metals are so critical to the US economy the the Federal Government retains a strategic stock pile of them. This program describes how these metals are produced and what they are used for that make them so valuable: copper, iron, lead, nickel, uranium and zinc. Written by
David Foss
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