Investor interest in rare-earth minerals is rising, a source of strength for shares in the rare-earth miner MP Materials. The stock rose Friday after jumping late Thursday following a Bloomberg report that the Defense Department might provide additional capital to boost production.

The U.S. trade "deal" with China highlights how dependent Americans are on Chinese rare earth minerals, creating an economic vulnerability.

In return, Trump said, the U.S. will provide China “what was agreed to,” including allowing Chinese students to attend American colleges and universities.