Bougainville Copper Limited is a mining company of Papua New Guinea that is listed on the Australian Securities Exchange. BCL operated the copper, gold and silver mine at the Panguna mine on Bougainville Island in PNG from 1971 to 15 May 1989, when mining operations were officially halted due to militant activity. The mine has remained closed since then. Mining giant Rio Tinto Group, which was historically Bougainville Copper Limited's major shareholder, exited on 30 June 2016 when it transferred its 53.8 per cent shareholding for distribution to the Autonomous Bougainville Government and the Independent State of Papua New Guinea. Wikipedia