lutetium, cassiopeium, Lu
chemical element, a rare-earth metal of the lanthanide series of the periodic table, that is the densest and the highest-melting rare-earth element and the last member of the lanthanide series, keemiline element, lantanoid, hõbevalge pehme metall, sulamistemperatuur 1652 ºC, tihedus 9,84 Mg/m3