Like its peers, Rio Tinto has been cutting costs, reviewing other projects and closing coal mines in Australia due to depressed commodity prices, high costs and the strong Australian dollar. MELBOURNE/SYDNEY, 29 Nov 2012 (Reuters) – Rio Tinto aims to axe $7 billion in costs over the next two years and sell more assets to cushion against weaker commodity prices, while at the same time beefing up output in its lucrative iron ore business.