A Toyota Prius uses around 1 kilogram.
Computer Hard Drives use around 10 grams
Electronic devices use between 5-25 grams
Wind Turbine Magnets use up to 2000kgs
from wikipedia:
There are two principal neodymium magnet manufacturing routes:
- The classical powder metallurgy or sintered magnet process
- The rapid solidification or bonded magnet process
Bonded Nd-magnets are prepared by melt spinning a thin ribbon of the Nd-Fe-B alloy. The ribbon contains randomly oriented Nd2Fe14B nano-scale grains. This ribbon is then pulverized into particles, mixed with a polymer and either compression or injection molded into bonded magnets.
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This process produces an extreme amount of hazardous by-products. At the primary production source in Baotau, According to Du Youlu of Baogang’s safety and environmental protection department, seven million tons of waste a year was discharged into the lake, which is already 100ft high and growing by three feet each year.
Jamie Choi, an expert on toxics for Greenpeace China, says villagers living near the lake face horrendous health risks from the carcinogenic and radioactive waste.
‘There’s not one step of the rare earth mining process that is not disastrous for the environment. Ores are being extracted by pumping acid into the ground, and then they are processed using more acid and chemicals.'