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The Japanese call rare earths as ¡°the seeds of technology.¡± The US Department of Energy calls them ¡°technology metals.¡± They make possible the high tech world we live in today everything from the miniaturization of electronics, to the enabling of green energy and medical technologies, to supporting a myriad of essential telecommunications and defense systems. They are the elements that have become irreplaceable to our world of technology owing to their unique magnetic, phosphorescent, and catalytic properties.

Rare earth elements are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium. Scandium and yttrium are considered rare earth elements since they tend to occur in the same ore deposits as the lanthanides and exhibit similar chemical properties. While named rare earths, they are in fact not that rare and are relatively abundant in the Earth's crust. What is unusual is to find them in quantities significant enough to support economic mineral development.