Neodymium

Neodymium

Neodymium is a chemical element with the symbol Nd and atomic number 60. It is a soft silvery metal that tarnishes in air. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach. It is present in significant quantities in the ore minerals monazite and bastnäsite. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. Although neodymium is classed as a "rare earth", it is a fairly common element, no rarer than cobalt, nickel, and copper ore, and is widely distributed in the Earth's crust. Most of the world's neodymium is mined in China.

Neodymium compounds were first commercially used as glass dyes in 1927, and they remain a popular additive in glasses. The color of neodymium compounds—due to the Nd3+ ion—is often a reddish-purple but it changes with the type of lighting, due to fluorescent effects. Some neodymium-doped glasses are also used in lasers that emit infrared light with wavelengths between 1047 and 1062 nanometers. These have been used in extremely high power applications, such as experiments in inertial confinement fusion.
Neodymium is also used with various other substrate crystals, such as yttrium aluminum garnet in the Nd:YAG laser. This laser usually emits infrared waves at a wavelength of about 1064 nanometers. The Nd:YAG laser is one of the most commonly used solid-state lasers.

Another chief use of neodymium is as the free pure element. It is used as a component in the alloys used to make high-strength neodymium magnets – powerful permanent magnets. These magnets are widely used in such products as microphones, professional loudspeakers, in-ear headphones, and computer hard disks, where low magnet mass or volume, or strong magnetic fields are required. Larger neodymium magnets are used in high power versus weight electric motors (for example in hybrid cars) and generators (for example aircraft and wind turbine electric generators).

Occurrence and production


Neodymium is never found in nature as the free element, but rather it occurs in ores such as monazite and bastnäsite that contain small amounts of all the rare earth metals. The main mining areas are in China, the United States, Brazil, India, Sri Lanka, and Australia. The reserves of neodymium are estimated at about eight million tonnes. Although it belongs to the rare earth metals, neodymium is not rare at all. Its abundance in the Earth crust is about 38 mg/kg, which is the second highest among rare-earth elements, following cerium. The world's production of neodymium was about 7,000 tonnes in 2004. The bulk of current production is from China, whose government has recently imposed strategic materials controls on the element, raising some concerns in consuming countries and causing skyrocketing prices of neodymium and other rare-earth metals. As of late 2011, 99 percent pure neodymium was traded in world markets for USD $300 to $350 per kilogram, down from the mid-2011 peak of $500/kg.

Neodymium is typically 10% to 18% of the rare earth content of commercial deposits of the light rare earth element minerals bastnasite and monazite.[citation needed] With neodymium compounds being the most strongly colored for the trivalent lanthanides, that percentage of neodymium can occasionally dominate the coloration of rare earth minerals—when competing chromophores are absent. It usually gives a pink coloration. Outstanding examples of this include monazite crystals from the tin deposits in Llallagua, Bolivia, ancylite from Mont Saint-Hilaire, Quebec, or lanthanite from the Saucon Valley, Pennsylvania. As with neodymium glasses, such minerals change their colors under the differing lighting conditions. The absorption bands of neodymium interact with the visible emission spectrum of mercury vapor, with the unfiltered shortwave UV light causing neodymium-containing minerals to reflect a distinctive green color. This can be observed with monazite-containing sands or bastnasite-containing ore.

Symbol		Nd
Atomic Number		60
Atomic Weight		144.24
Oxidation States		+3
Electronegativity, Pauling		1.14
State at RT		Solid, Metal
Melting Point, K		1294
Boiling Point, K		3341

Appearance and Characteristics

Harmful effects:

Neodymium is considered to be moderately toxic.

Characteristics:

• Neodymium is a soft, bright, silvery white metal. It is one of the lanthanide rare earth metals. It forms a flaky oxide coating in air. Unlike many metal oxide layers, this one does not protect the metal from further oxidation.
• Neodymium has two allotropic forms, transforming from hexagonal to body-centered cubic above 800K (527 oC).
• Neodymium usually exists as a trivalent ion, Nd3+, in its compounds. Most of its salts are pale purple in color.

Uses of Neodymium

• Neodymium is used with iron and boron to create powerful permanent magnets, also called NIB magnets. NIB magnets are used in computers, cell phones, medical equipment, toys, motors, wind turbines and audio systems. 
• Neodymium is used as a crystal (neodymium-doped yttrium aluminum garnet) in lasers. These ND:YAG lasers have numerous applications. For example, they are used in medicine to treat skin cancers and for laser hair removal; and in industry they are used to cut and weld steel.
• Neodymium is used to make specialized goggles for glass blowers.
• The metal is also used in a spark producing alloy (misch metal) for cigarette lighter flints.
• Neodymium salts are used to color glasses and enamels.