This presentation details the various factors behind the huge 25-fold increase in the copper resource base over the last hundred years. It has data on discovery rates, head grades and mining costs from 1900 to 2009. It also shows key innovations in exploration, mining, processing and transport that have transformed the industry.
The key message is that engineers (and scientists) and geologists acted as equal partners in growing the copper resource base over the last century. Assuming that the industry continues to explore and innovate, the world will not run out of copper anytime soon. A similar story applies to other commodities.