MELBOURNE, Australia (

TheStreet

) --

Rio Tinto

(TK) - Get Report

, the world's third-largest mining company, blamed the drop in metal and mineral prices for a drop in the company's first-half profit of nearly two thirds.

On Thursday, the company reported a net profit of $2.5 billion for the six months ended June 30, down 65% from a year earlier. Its numbers were similar to those of rival miner

BHP Billiton

(BHP) - Get Report

, which last week announced a 61.8% profit decline for the first half of the year, which it also blamed on falling commodity prices.

Rio Tinto was guarded in its forecast for the rest of the year, noting uncertainty in whether recent gains in commodity prices would be sustained.

"However, the expectation that development in emerging markets will generate underlying strength in metals and minerals demand over the long term remains broadly unchanged," Chairman Jan du Plessis said in a statement.

Rio Tinto shares, which are traded on the Australian Stock Exchange, closed at 58.03 Australian dollars before the company's announcement. Shares of BHP Billiton, which is also traded on the ASX, were up by 1.1% to AUD $37.13.

-- Written by Ty Wenger in New York

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