Exhibit 99.1 News Release – November 7, 2024 Arcadium Lithium Releases Third Quarter 2024 Results PHILADELPHIA and PERTH, Australia, November 7, 2024 /PRNewswire/ -- Arcadium Lithium plc (NYSE: ALTM, ASX: LTM, "Arcadium Lithium" or the "Company") today reported results for the third quarter of 2024. As a result of its pending acquisition by Rio Tinto, announced on October 9, 2024 (the "Transaction"), and as is customary during such transactions, Arcadium Lithium will not hold an earnings conference call in ...