(Mo) is a refractory metallic element used principally as an alloying agent
in steel, cast iron, and superalloys to enhance hardenability, strength,
toughness, and wear and corrosion resistance. Molycorp operates one of the
handful of molybdenum mines throughout the world near Questa, New Mexico.
Aside from being mined as a primary mineral, it is also recovered as a by-product
of copper mining.