filtering and processing techniques before China became dominatnt in this field?
1950-1980s: The US was a global leader in rare earth mining and processing. The Mountain Pass Mine in California was one of the world's largest producers of rare earth elements. The US developed and used advanced separation and purification techniques, especially solvent extraction, to process rare earths.
1980s-1990s: Shifted to China. Chinese leaders in the 1980s and 1990s prioritized rare earths as a strategic industry. China sent students and engineers abroad to study mining, metallurgy, and chemistry including in the US, Japan and Europe, then brought the knowledge back. Western firms, including General Motors outsourced rare earth magnet production to Chinese firms, such as China's state-owned enterprises. For example, Magnetics from GM was sold to China in the 1990s, bringing expertise to China. Some US and Japanese companies licensed technologies, formed joint ventures, or sold rare earth equipment or subsidiaries to Chinese firms.
Certainly, western companies were seeking cheap processing. As environmental regulations tightened in the US, rare earth processing became expensive and plitically difficult. This, combined with state-led industrial policy and low labor/envirnment costs, enabled China to dominate the field by the early 2000s.
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I am speachless.
