World's largest mining firm records worst loss in its history

The world's largest mining firm has been severely damaged by a bad bet on shale, a dam disaster in Brazil and a commodities slump.

BHP Billiton, the world's largest mining firm by market value, reported a company record net loss of $6.4 billion for the year ended June 30.

"While commodity prices are expected to remain low and volatile in the short to medium term, we are confident in the long-term outlook for our commodities, particularly oil and copper," CEO Andrew Mackenzie said in a statement.

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