Vale to take $4.2 billion writedown for nickel, aluminum assets

　　Brazil's Vale SA, the world's No. 2 mining company, will write down the value of nickel and aluminum assets by $4.2 billion, according to a securities filing on Thursday.

　　The company will book the non-cash, pre-tax charge in the fourth quarter, the filing said. Among the projects affected by the writedown is On?a Puma.