Element 65 · Lanthanide (Rare Earth)
Terbium
Terbium is essential to neodymium magnet performance at high temperatures — and is one of the rarest production rare earths.
Element Facts
SYMBOL
Tb
ATOMIC NO.
65
ATOMIC WEIGHT
158.93
CATEGORY
Lanthanide (Rare Earth)
PERIOD
Period 6
GROUP
Group 3
Historical Uses
Terbium was discovered in 1843 by Swedish chemist Carl Gustaf Mosander, who separated the mineral yttria (named after Ytterby, a village near Stockholm) into three fractions. He named the components yttrium, erbium, and terbium — the latter two both derived from "Ytterby." It was one of several rare earth elements whose isolation from yttria kept chemists occupied throughout the 19th century.
For over a century, terbium had no significant industrial application. The rare earths as a group were notoriously difficult to separate into pure form, and uses were largely academic. The development of ion-exchange chromatography after World War II finally made it possible to produce reasonably pure rare earth metals economically.
Terbium's most visible modern use is in green phosphors for colour television and fluorescent lighting — terbium-activated lanthanum phosphate produces an intense green emission. It is also used in magneto-optical storage materials and, increasingly, in solid-state green and white LEDs. Like dysprosium, terbium is added to neodymium magnets to improve high-temperature performance.
Overview
Terbium is element 65, named after the Swedish village of Ytterby (which gives its name to four elements: yttrium, terbium, erbium, and ytterbium). It is one of the rarest commercially produced rare earths.
Current Uses
Terbium additions to NdFeB magnets dramatically improve their high-temperature performance — critical for EV motors operating at 150°C+. Terbium-doped phosphors in fluorescent lamps and LEDs (green emission). Terfenol-D (terbium-iron-dysprosium) is the most magnetostrictive alloy known, used in sonar and precision actuators.
Not Commercially Viable for Scrap
Why QuickStop Metals doesn’t buy Terbium:
Terbium is one of the most strategically constrained rare earths. Recovery from magnets and phosphors requires specialist processing not available in general scrap operations.
Price Context
Terbium oxide has reached $1,500–3,000/kg in recent years.