Apple and MP Materials unveiled a $500 million deal to bolster the iPhone maker’s domestic supply chain for rare‑earth magnets.

Shares of MP Materials are surging in early trading Tuesday after Apple said it would invest $500 million in the owner of the U.S.’s only operational rare earths mine.

MP Materials unveiled a multibillion-dollar deal with the U.S. government on Thursday to boost output of rare earth magnets and help loosen China's grip on the materials used to build weapons, electric vehicles and many electronics.