Bayan Obo Mining District

Bayan Kuang (白云 矿区"Rich Mine"; Baiyun Kuang Qū ) is a municipality of the prefecture-level city of Baotou in Inner Mongolia Autonomous Region of the People's Republic of China. Bayan Kuang has an area of ​​303 km ² and has a population of 20,000.

Mines

In the north, Bayan Kuang found in metamorphic rocks of the Upper Proterozoic rich deposits of rare earths, which are surface mined.

The mines were discovered in the 1920s and contain ores of iron, rare earths and niobium. Here are the largest iron ore deposits of China with more than one billion tons of reserves. The reserves of ores of rare earth exceed 35 million tons. These consist mainly ( 80%) of Bastnäsit and monazite with a rare earth content between 1 and 6.2 %. Since the thorium content in the monazite from this source is only 0.26% to as the rare earth metal oxide, and phosphate content is more than 98 %, it is a desired grade for the production of rare earth metals. Also the Bastnäsit has a thorium content of only 0:02 to 0:28 %.