Shares of Rio Tinto were falling 2.5% to $53.95.
According to a report from the Daily Mail Rio Tinto is preparing a bid of about $8 a share for Turquoise Hill. Rio Tinto already owns 50.8% of the Vancouver-based company, the bid would be for the 49.2% it doesn't already own.
News of the possible acquisition comes shortly after Turquoise Hill reported issues with its Oyu Tolgoi copper and gold mine in Mongolia. Progress on that project has been held up by Rio Tinto's inability to reach an agreement with the Mongolian government.
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