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Rare
Earth: An Introduction Entering the 21st century, the pace of industrial and economic globalization is speeding up. As China enters the WTO, the Chinese government has begun the implementation of its policy to develop its western regions. Located in western China, Baotou is famous for its rich rare earth resources, thus being named "The Mother Lode of Rare Earth". In 1992, Chinese President Deng Xiaoping pointed out, "There is oil in the Middle East; there is rare earth in China¡." That same year, the State Council approved the establishment of the Baotou Rare Earth Hi-tech Industrial Development Zone. During his 1999 visit to Baotou, President Jiang Zemin wrote, "Improve the development and applications of rare earth, and change the resource advantage into economic superiority." Then President Jiang repeated the strategic importance of developing China's rare earth industry, which has caught worldwide attention. The reason why rare earth, a small industry with annual consumption of only 75,000 tons REO and a market value below US$100 million, has been given attention by Chinese leaders at all levels is due to its uses in modern hi-tech industries because of its special chemical and physical properties. As a matter of fact, rare earth has been listed in the category of strategic elements in many countries, such as the USA and Japan. Some experts predict technological innovation with the global development and application of rare earth. What
is Rare Earth? Rare earth is a group of 17 elements including 15 lanthanides (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) located in the Periodical Table from atomic number 57 to 71, and Sc numbered 21 and Y numbered 39. According to the differences in chemical and physical properties of rare earth elements, rare earth is usually grouped into two subgroups: light rare earth or ceric group including the first 7 lanthanides from La to Gd, and heavy rare eath or yttric group including the rest of the lanthanides, Sc and Y. Rare earth was first found by Finnish scientist Gadolin in 1794, and he named it Rare Earth, thus leaving a misnomer for the group of elements that is not earth at all, but a group of typical metallic elements with chemical activity only next to alkaline and alkaline earth metals. And rare earth is not rare at all, because the proven reserves have reached 100 million tons REO. Based on its present annual consumption (75,000 tons REO), the proven reserves of rare earth can serve the world for over 1000 years. Rare earth exists in mineral forms in nature. The most commonly used rare earth minerals are bastnasite, a kind of rare earth fluoro-carbonate, and monazite, a kind of rare earth phosphate, and both minerals are rich in light rare earth. Xenotime and ion-adsorption clay minerals are the major source for heavy rare earth, and the ion-adsorption clay minerals are only found in China. Up till now, the world's largest deposit for light rare earth is Baiyunebo deposit located in Baotou, Inner Mongolia, China. Rare earth in the deposit coexists with iron and niobium and other elements and is recovered as a byproduct of iron mining. Rare earth concentrates with 50% to 65% REO are obtained by beneficiation, but the concentrates can not be directly used, and must be processed into rare earth chloride, carbonate or mischmetal which are called primary products. Some of these products are used in traditional industries such as metallurgy and chemical engineering, and most of them are now processed into individual rare earth metals or oxide for hi-tech applications. The unsaturated 4f electronic structure of rare earth elements makes them have special properties of luminescence, magnetism and electronics, which could be used to develop many new materials, such as phosphors for TV's, lamps and X-rays, magnetic and magnetostrictive materials, hydrogen storage materials and auto-emission catalysts. Rare earth elements have been called the treasure house of new materials in the 21st century. Rare Earth Resources As mentioned above, rare earth is not rare. The content of rare earth in the Earth's crust is 0.0236%, much richer than many commonly used elements such as Cu(0.01%), Zn(0.005%), Sn(0.004%), Pb(0.0016%) and Ni(0.008%). The rich resources of rare earth are the strong support to the development of hi-tech industries in the future. The following lists the data for world's proven rare earth reserves, reserve base and concentrate production in 1999.
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