Officials at top miner Rio Tinto have sold their 28% majority stake in aluminum products maker Constellium NV for $330 million. Rio Tinto will hang on to 9.2% of the company it acquired during its $38 billion Alcan Inc. takeover in 2007; the Amsterdam-based Constellium makes aerospace, packaging and automotive industry products.

The Alcan deal, at the peak of the aluminum market, was disastrous for Rio Tinto, leading to $30 billion in write-downs, as demand for the metal slumped amid soaring Chinese output; in Q1 2013, Rio CEO Tom Albanese subsequently resigned.

Since then, officials at the Anglo-Australian miner have sold off or idled numerous underperforming aluminum assets to cut debt that swelled to $19 billion in 2012 to protect its single-A credit rating. These include its majority stake in Australian copper-gold mine Northparkes to China Molybdenum Co. for $820 million.

Last month, meanwhile, Rio Tinto agreed to sell its Clermont thermal coal mine in Australia’s Queensland province to Glencore Xstrata plc and Sumitomo Corp. for $1.02 billion. Rio Tinto, however, stopped short of selling its loss-making Pacific Aluminum business in August, citing bad market conditions.