MELBOURNE (Reuters) -U.S.-based miner Albemarle said it had dumped a A$6.6 billion ($4.16 billion) buyout bid for Australian lithium developer Liontown Resources, in part because of "growing complexities" around the transaction. Albemarle has withdrawn its indicative proposal, the companies confirmed in separate statements that came days after Hancock Prospecting, an iron ore miner controlled by Australia's richest person, Gina Rinehart, raised its stake to 19.9% of Liontown. That shareholding would likely have been enough to block the Albemarle bid of A$3 a share.