Terbium – 65
Terbium is a heavy rare earth element that is one of the least available and most valuable of the group. It is found in small concentrations in cerite, gadolinite, monazite, xenotime, and euxenite.
Magneto-optic recording of data for computers. Green colour for LCD screens and fluorescent lighting. Mixed with europium to make white backlighting for LCDs and tri-phosphor lightbulbs. Manufacture of Terfenol-D for naval sonar systems. Stabilizes magnets for reliable performance at high temperatures. Used in doping magnets for hybrid car regenerative braking systems and motors. High-strength magnets for microphones, speakers, hard drives, wind turbines, and hydro power turbines. Glass polishing for cathode ray tubes (CRT), plasma (PDP), and liquid crystal (LCD) screens.