稀土是17种 稀有元素的统称。
The 17 rare-earth elements are
cerium (Ce), dysprosium (Dy),
erbium (Er),
europium(Eu), gadolinium (Gd),
holmium (Ho), lanthanum (La),
lutetium (Lu), neodymium(Nd),
praseodymium (Pr), promethium (Pm),
samarium (Sm), scandium (Sc),
terbium (Tb), thulium (Tm),
ytterbium (Yb), and yttrium (Y).
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