Apple's $500 million investment in MP Materials is making headlines across the U.S. tech and defense sectors. In a bold move to boost American-made rare earth production, Apple is partnering with MP Materials—backed by a $400 million Pentagon deal—to reduce dependence on China.

MP Materials, which runs the only American rare earths mine, announced a new $500 million agreement with tech giant Apple on Tuesday to produce more of the powerful magnets used in iPhones as well as other high-tech products like electric vehicles.

The Pentagon is slated to become the largest shareholder in rare-earth miner MP Materials. The Department of Defense has agreed to buy $400 million of MP's stock and provide the Las Vegas-based miner with a $150 million loan,