1/23/2024 0 Comments Balarama pdf 2020 download![]() ![]() However, other types of resources such as ocean bottom sediments, waste rocks in closed mines, river sediments, industrial wastes like red mud, coal, and fly ash have proved to be containing significant amounts of these elements. These metals occur in primary deposits associated with igneous and hydrothermal processes, and secondary deposits concentrated by sedimentary processes and weathering. However, countries such as USA, Australia, India, and Kazakhstan also extract and refine significant quantities of REE. ![]() At present, China is responsible for 80% of global REE production. The future of the world’s green technologies depends upon their availability and supply. ![]() All these metals occur together in different types of REE deposits such as carbonatites, alkali syenites and monaziterich placers, and are found in more than 250 minerals in the Earth’s crust. Rare earth elements (REE) include the lanthanide series (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) plus Sc and Y. ![]()
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