An owner of Uganda's only tungsten mine is suing the International Tin Association for defamation, saying the certifier wrongly accused it of trading in conflict minerals.
The Catalao mine was not in operation for two months as the company worked to bring its mine tailings dam into compliance with new Brazilian regulation.
Vale said risk of a new dam break as a consequence of an unstable embankment at Gongo Soco open pit, in the southeastern state of Minas Gerais, are now minimal.
President and CEO Mark Bristow said the company expected to complete a feasibility study for the project, which could extend the life of the mine into the 2030s.