July 31 (Reuters) - The main union at Chile's Caserones mine has rejected operator Lumina Copper's final contract offer and workers have approved strike action, the union's president said on Tuesday.
The strike was scheduled to begin on August 7 after a compulsory mediation period. Lumina is controlled by a partnership of JX Holding and Mitsui Mining and produces just over two per cent of Chile's total annual copper output.
The company did not reply to a request for comment.
The strike vote coincided with the threat of a strike at the country's biggest copper mine, Escondida, and a walkout by workers at state miner Codelco's Chuquicamata facility.
(By Aislinn Laing; Reporting by Antonio de la Jara)