July 16 (Reuters) - MP Materials ( MP ) said on

Wednesday it would sell $500 million of its common stock, a day

after the U.S. rare earths miner inked a supply deal with Apple ( AAPL )

.

Shares of MP Materials ( MP ) fell 5.8% in extended trade. They

have surged 275% so far this year, giving the company a market

value of $9.57 billion.

The $500 million agreement with Apple ( AAPL ) is a coup for MP and a

rare investment by a tech company aiming to reduce its supply

risks for rare earth magnets.

The Las Vegas-based company also signed a

multibillion-dollar agreement with the U.S. Department of

Defense last week as the government seeks to reduce its reliance

on China, which restricted rare earths exports in April in

response to President Donald Trump's tariffs. Though the U.S.

and China reached a deal in June that has resolved much of the

rare earths dispute, broader trade tensions continue to

underscore demand for non-Chinese supply.

The Pentagon deal did not require MP Materials ( MP ) to issue

stock for the general public.

MP said it intends to use net proceeds from the offering to

fund growth opportunities and for general corporate

purposes.

The company said it would grant underwriters a 30-day option

to purchase up to an additional 15% of its shares.

J.P. Morgan and Goldman Sachs are acting as lead joint

book-running managers in the stock sale, while Morgan Stanley is

another book-running manager.

(Reporting by Sumit Saha in Bengaluru; Editing by Devika

Syamnath)