chapter  3
Resource Processing
Pages 98

In the overall rare-earth extraction flow sheet, the term resource processing refers to the group of unit operations, comprising both physical and chemical processing, used to obtain from the as-mined ore a compound that is either an end product in itself or an interprocess intermediate for the subsequent processing to the metal or alloy or other compound. Usually, these processes accomplish sequential removal of impurity compounds from the material being processed. In the case of rare earths, the resource processing involves not only the operations that result in such impurity removal but also special operations that achieve the difficult task of separating the considerable number of naturally co-occurring rare-earth elements (REEs) from one another.