Net income in the three months ending Sept. 30 was $1.67 billion (U.S.), compared with $4.94 billion a year earlier.
The drop in profits came after the price of iron ore dropped to three-year lows.
“Vale’s performance in the third quarter reflected the challenges resulting from volatility of falling prices that happened as a result of the slowing of growth in the world economy,” the company said in a statement.
Falling prices and weak demand in China, Vale's largest market, have led the Rio de Janeiro-based company to delay spending, close operations and consider cuts to investments and dividends, according to a Reuters article.
The company recently announced it is moving the completion date for its $2-billion Clean AER project in Sudbury from the end of 2015 to the beginning of 2016.
It also announced Oct. 18 that operations at the Frood section of Stobie Mine will be suspended by the end of the year.
The company has also announced the suspension of operations at three Brazilian iron ore pellet plants, according to Reuters. Earlier this week, the company added the Simandou high-grade iron ore deposit in Brazil to the list of projects on hold.