These elements are those that compose the lanthanide series on the periodic table, as well as scandium and yttrium. The first rare earth mineral, a composite of rare earths and other elements, ever discovered was known as gadolinite. It was discovered outside a village named Ytterby, Sweden at a rock quarry in 1787. This mineral was a compound of yttrium, cerium iron and other substances. Many subsequent discoveries of rare earths have derived their names from this region. Several more rare earths were discovered throughout the 19th century. These discoveries continued until the full complement was known by the end of the 20th century.
Until the middle of the 20th century, all rare earth deposits and mining activities were located in Brazil and India. In the 1950’s, South Africa became leading producer of these elements. Then mines in California began to produce substantial quantities of these minerals until the 1980’s. However, if you want to buy rare earth magnets these days, your supplier will most likely have acquired the raw materials from China, which now produces some 97% of the rare earths on the market today.
There is growing concern that the development of rare earth magnets and other applications for rare earths may be hampered by a slowdown, or an insufficient acceleration, in the production of these elements. Worldwide demand increases every year, since these materials are crucial in the manufacture of a number of electronic devices and in magnets used in industrial applications. Mining capability at present mines has already peaked and will not be able to meet the demands of coming years unless new sources are developed.
Concerns about this dilemma have been heightened by the actions of the Chinese government, which has stated already that it intends to cut back on its output. Even if the other mines in the world were to drastically increase output, they could not match the loss that would be created even by the smallest draw down of Chinese mining activities. Searches for new deposits are ongoing around the world as nations seek sources from which to buy rare earth magnets. The United States is believed to possess considerable deposits of these elements but does not have many active mines in place.


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