Shares of MP Materials soared 50% Thursday morning after the rare earths miner announced a multibillion-dollar agreement with the Department of Defense.

The $400 million investment will create a domestic supply chain for materials used in fighter jets and missiles.

Rare earth materials end up in things such as magnets for electric motors and in navigation equipment. For the Pentagon, supplies they are are a matter of national security. An F-35 has more than 900 pounds of rare earths in it.