The deal would see the Defense Department take a 15% stake in MP Materials and spend billions of dollars investing in the company and purchasing its output.

When China began its crackdown on the sector some fifteen years ago, there were hundreds of miners and processors. By 2013 ten producers controlled almost all mining. Today, there are just two state-owned giants: China Rare Earth Group and China Northern Rare Earth Group High-Tech (600111.SS).

MP Materials has announced plans to expand rare earth mining and processing operations as Washington seeks to end its dependence on Chinese supplies.