RARE EARTHS AND CRITICAL ELEMENTS IN ORE DEPOSITS: AN ECONOMIC INTRODUCTION (Invited Presentation)

A critical element, as the term has come to be used, provides essential functionality to a modern engineered material, has few if any close substitutes and is subject to supply risk. The rare earths became the most prominent of these elements following the spike in their prices in 2010-11. But other minor and technology metals are critical elements, too. By custom, major metals such as iron, copper and aluminum are not considered critical elements, even though to some users they satisfy the definition of a critical element. This talk provides an economic introduction to rare earths and other critical elements.