When there's too much demand for the offer, the price simply goes up. It's basic economics.  I don't think that $20 - $30 is needed long term for now, but could copper spike like silver in 2011 or wood, lithium and magnesium in the last years?  Maybe, $25 lbs copper is like $50 oz silver, but I don't think the copper demand would change overnight.   At higher prices, majors would invest to increase capacity and attempt to balance the market.  I did not see any studies, but there's probably plenty of lower grade projects out there that could eventually come online if copper would be closer to $15k per ton.  The only question for me is can majors compensate enough via expansions to meet the demand until those new mines are ready for action?  We are also seeing more and more disruption around the world.  This could change demand overnight.  Who knows what can happen.  In any case, I think it's good to hold copper!

MoneyK