The Resolution project is situated in Arizona, US, in the area of the former Magma (Superior) copper mine. In 2001, an agreement was signed with BHP Billiton Base Metals which allowed Rio Tinto to earn a 55 per cent interest in the project by spending US$25 million over six years. Rio Tinto completed earning its 55 per cent interest in the project in early 2004. Preparatory work is underway to begin dewatering the old Magma mine with a view to developing shafts in the future.