A heavy rare earth added to magnets so they hold their strength at high temperature.
A heavy rare earth element (atomic number 66) added to neodymium magnets to improve temperature stability and resistance to demagnetization. Dysprosium is one of the most critical and valuable rare earths due to limited supply and growing demand for EV motors.
Dysprosium is what lets an EV traction motor survive under load, and it is far scarcer than the light rare earths. Deposits carrying meaningful heavies command attention disproportionate to their size.
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