Resources can never run out

In 1980, Paul Ehrlich, biologist and author of “The Population Bomb” (1968), made a bet with technological optimist Julian Simon that the prices of five commodities would increase over the next decade.

The commodities were copper, chromium, nickel, tin, and tungsten, and Prof Ehrlich lost.

Had “The Bet” been held over a different decade, Ehrlich may have won – but the point is the alarmist cause usually over-estimates the rate or extent of resource depletion. For instance, Peak Oil – the maximum annual rate of oil production - was supposed to have occurred most recently in 2010. It didn’t, and it may not for another generation, this time because of the shale gas revolution.

Intuitively, resources must become progressively depleted as more are extracted. But that is not what happens in practice. In 1924 it was predicted that copper would last 20 more years, and annual global production at that time was less than 2 million tonnes. Today that figure is around 18Mt, and is continuing to increase. To explain this paradox: as the price of minerals increase, so does the availability of mineral resources, at a lower grade or higher cost of extraction.   

Even so, a time must come when minerals run out, or – more accurately - become so expensive compared to the next best alternative that no more will be extracted. Indeed so, eventually. Copper is being replaced in some applications by fibre optics; or it is being used more efficiently, e.g., when alloyed with rare earth elements in electro-magnets; and copper is amenable to recycling.

Staying with copper, which is only weakly substitutable by other metals, submarine volcanism in places like the Kermadec arc is continuously pouring metal-rich fluids onto the seafloor. While the lifting of ore from the seafloor at water depths exceeding 1km poses a significant engineering challenge, we predict a time will come when this source of copper will be mined, and there is lots of it.