Selenium ingot ,Selenium grain,Selenium powder 1, 99.5% min purity 2,shape :ingot/powder/ selenium isotope / selenium 74 Selenium ingot ,Selenium ... grain,Selenium powder 1, Physical character:Atomic Weight: 78.96Electronegative: 2.48Density: ρ=4 ... Pb & Ni is bellow 1 ppm.3, Physical Size:Virgulate, Powder.4, Usage:It is mainly used in the preparation of ...