Neodymium was discovered by Carl Auer Freiherr von Welsbach, an Austrian chemist, in 1886 when he separated it and the element praseodymium from a compound known as didymium. He named neodymium from the Greek neo meaning new and didymos meaning twin.
Neodymium metal has a bright silvery colour and metallic lustre. It is a reactive rare earth that quickly tarnishes in air, forming an oxide that spalls off and exposes the metal to further oxidation. It is never found in nature as a free element. Rather, it occurs with other rare earth elements in minerals such as monazite and bastnaesite.
Applications of Neodymium:
- Rare Earth Magnets: Neodymium magnets are the strongest permanent magnets known. They appear in products such as microphones, loudspeakers, ear buds, hearing aids, guitar pick-ups and computer hard drives. They are found throughout hybrid cars, in industrial motors, air conditioners, elevators, industrial tools and in wind and tidal electricity turbine generators. High-temperature grade neo-magnets can be made by introducing the rare earths terbium or dysprosium to the alloy, thus making magnets that will operate at up to 200˚C, and enabling the electric car.
- Glass and Ceramics: Neodymium glass is becoming widely used in incandescent light bulbs to provide a more ‘natural' light, as it filters out yellow wavelengths and results in a whiter light more akin to sunlight. Neodymium is similarly used in welding and glass-blowing eye protection and a neodymium specialty glass has been patented for use in automobile rear-view mirrors to reduce glare at night.
- Science and Medical: Neodymium is used as a dope in yttrium- aluminum-garnet (YAG) lasers for medical applications, drilling, welding and material processing. Naturally occurring neodymium isotopes are used by geologists to describe the origins of different magmas, and samarium-neodymium isotopes can be used to determine the age of rocks and meteorites. Neodymium has an unusually high heat capacity at the temperature of liquid-helium, so it is useful in cryocoolers.