Atomic symbol - Tb Atomic weight - 158.92534 Atomic number - 65 Electron configuration - 2-8-18-27-8-2 Oxidation states - +3 State of matter - solid Heavy metal-brittle Discovered in 1843 by Carl Gustaf Mosander Boils at 3041 .C, melts at 1360 .C Notes: Terbium has a silvery-white color.