Two months ago Garimpeiro said he was taken by BHP’s assessment at the time that the supply deficit in copper previously expected to emerge in the final third of the 2020s could well come earlier.

What’s more, the supply deficit could be “pronounced’’ in the medium–term (five years).

Supply deficits force higher prices, and if they are pronounced, so too is the price response. As it is, we’re getting a taste of what that could mean for copper as the price of the red has taken off to $US4.40/lb mid-week.