With players like this one which will be a top 5 copper producer by 2019/20 we mb aren't able to lift the copper price like iron ore... 320kt new copper/year just coming on stream from this one:
https://beta.theglobeandmail.com/globe-investor/investment-ideas/worlds-newest-major-copper-mine-is-a-loner-until-prices-rebound/article34229890