MP Materials rises after report Apple to invest $500 million in US mine

** Shares of U.S. rare earths miner MP Materials MP.N jump 12.3% to $54.50 premarket

** Fox Business reports Apple AAPL.O is expected to announce a $500 million commitment to MP Materials, citing sources familiar with the matter

** Agreement includes plans for Apple to purchase American-made rare earth magnets from MP Materials' Texas facility report adds

** Fox Business says the two companies will also build another factory in Fort Worth, Texas to produce magnets and a new recycling facility in Mountain Pass, California

** As of last close, MP stock is up over 211% YTD