Origin: ModL: so named (1863) by F. Reich (1799-1882) & H. T. Richter (1824-98), Ger metallurgists < L indicum, indigo + -ium, because of the two indigo lines in its spectrum
See indium in American Heritage Dictionary 4
noun Symbol In
Origin: + -ium (so called from the indigo-blue lines in its spectrum).
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