Rare earths are widely used in the new energy, new materials, energy conservation, environmental protection, aerospace, electronic information and other fields is indispensable to modern industry important factor known as "industrial monosodium glutamate", to protect the precious rare earth resources and the ecological environment to prevent the rare earth resources, prevent the rare earth prices slump too cheaply to protect rare earth industry chain all healthy, smooth running national rare earth build-up is particularly important.