12 a view of a brine pool of a lithium mine on the atacama salt flat in the atacama desert chile august 16 2018reutersivan alvaradofile photo santiago april 21 reuters  shares in chiles top two lithium miners sqm sqmasn and albemarle corp albn slid on friday after the andean country which has the worlds largest reserves of the battery metal unveiled a plan to nationalize the industry the move would see chile the worlds second largest lithium producer shift to a model with the state holding a controlling interest in all new lithium projects through a public company that would partner with private mining firms the bid for state control in chile reflects a wider wave of lithium nationalism around latin america home to the socalled lithium triangle which holds the worlds largest trove of the metal essential for electric vehicle batteries it poses a fresh challenge to electric vehicle ev manufacturers scrambling to secure battery materials mexico nationalized its lithium deposits last year and indonesia banned exports of nickel ore a key battery material in 2020 chiles young progressive president gabriel boric said late on thursday in his announcement that the country would not cancel existing contracts though it would try to negotiate with mining firms to voluntarily shift to a publicprivate model in early trading on friday chilean firm sqms uslisted shares slid 62 while albemarle was down 25 sqms lithium contract in chile is set to expire in 2030 and albemarles in 2043 giving it more insulation from the potential move mining shares in london fell sharply too rio tinto riol dropped by as much as 5 at one point to its lowest in almost a month and was last down 47 shares in rival anglo american aall fell 4 on the day making the basic resources sector the worst performer in europe in neighboring countries in the lithium triangle which spans chile argentina and bolivia governments are increasingly pushing for a greater public sector stake in mining of the metal and are seeking to develop a nascent battery sector argentine state energy firm ypf has got into lithium while bolivia has long maintained strict control over its huge though largely untapped resources it recently gave out a lithium tender to a chinese consortium including battery giant catl mexicos president andres manuel lopez obrador and bolivias luis arce have touted the idea of a regional lithium opec to coordinate on lithium policy and benefit local economies defending bolivian lithium is defending the homeland bolivias arce tweeted earlier this week reporting by alexander villegas and ernest scheyder writing by adam jourdan editing by jan harvey