USA Rare Earth named Serra Verde Group Chief Executive Thras Moraitis to lead the combined company following completion of a $2.8 billion combination of the two mining companies. Moraitis's appointment is effective October 1, the company said Monday.

He will succeed Barbara Humpton, who is retiring from the company and board at that time. The company also named Michael Blitzer, current board chair, as executive chairman, effective immediately.

USA Rare Earth in April agreed to buy Serra Verde, which owns a rare-earth mine and processing plant in Brazil, in a move that would strengthen its mine-to-magnets supply chain at a time of heightened geopolitical tensions between the U.S. and China. The deal, in a combination of cash and stock, is expected to close by the end of August.