ERBIUM

Er″bi‐um (?), n. [[NL. from Ytterby, in Sweden, where gadolinite is found. Cf. Terbium, Yttrium, Ytterbium.]] (Chem.) A rare metallic element associated with several other rare elements in the mineral gadolinite from Ytterby in Sweden. Symbol Er. Atomic weight 165.9. Its salts are rose-colored and give characteristic spectra. Its sesquioxide is called erbia.