Panguna’s remaining reserves are estimated at 5.3 million tons of copper and 19.3 million ounces of gold, which would be worth about $160 billion at today’s prices. However, the mine was closed down in 1989 under the ownership of Rio Tinto Group due to local protests over environmental damage and revenue distribution, which degenerated into a civil conflict that killed as many as 20,000 people. A decade ago, Rio gave away its majority interest in the firm which then held the license.