Two facts account for the disparity: The metals are relatively easier to access in China, and China's unregulated wild-cat mines don't need to pass on any environmental mitigation costs to their customers abroad.
Many of the most critically affected species are found in China, including Magnolia phanerophlebia, of which only around 200 trees are estimated to exist in thewild and Magnolia sinica, believed to have a single population of fewer than 10 mature trees.