Critical Rare Earth Elements 

What are “Critical Rare Earths”? 

According to Dr. Alex King, U.S. Department of Energy, Ames Lab Director, critical refers to “the stuff you need the most but can’t get enough of.” In 2011, the US Department of Energy completed a study entitled, Critical Material Strategy. The study reviewed rare earths based on their role in clean energy as well as supply risk. They identified Neodymium (Nd), Europium (Eu), Terbium (Tb), Dysprosium (Dy) and Yttrium (Y) as critical rare earths (CREE) for both the short and long term. Rare Element includes Praseodymium (Pr) in this list because of its ability to be substituted for Neodymium in high-intensity permanent magnets.