There is, supposedly, a neat choreography to copper and gold prices. When one rises, the other tends to fall. In an economic downturn, for instance, gold climbs as investors seek a haven. Copper prices dip as manufacturing and construction slow. But these are unusual times, and gold and copper are moving in unusual ways. Rather than continue their customary do-si-do, they are leaping upwards together.

The price of copper surpassed $6,000 a tonne in June, up about 30% since the depths of March. Gold this month topped $1,800 an ounce, approaching a record reached in 2011. Many analysts reckon it may exceed $2,000 this year or next. As the world continues to reel from covid-19, the economic outlook is uncertain and the recovery uneven from one country to the next. For those betting on gold and copper, this has proved a winning formula.