稀土是化学性质十分相似而又较难分离的17个元素的总称,它包括元素周期表中的15个镧系元素及同族的副族元素钪和钇。“稀土”在地球上既不“稀”也不是“土”,在地壳中的含量并不少,总储量约占地壳的0.016％,超过人们常见的元素铜、锡、铅等。稀土的性质也不象“土”,是典型的金属,具有银灰色的金属光泽。自1794年发现第一个稀土元素钇以来已有200多年的历史,随着人类社会的进步,科学技术的发 Rare earth is chemically very similar and more difficult to separate the 17 elements in general, which includes the periodic table of 15 lanthanides and the same sub-group of elements scandium and yttrium. “Rare Earth” is neither “thin” nor “earth” on Earth. It contains not less than 0.016% of the earth’s crust and more than common elements of copper, tin and lead. Rare earth is not the nature of “earth” is a typical metal, with a silver-gray metallic luster. Since the discovery of the first rare earth element yttrium in 1794, it has been more than 200 years old. With the progress of human society, the development of science and technology