Aluminium prices are at heights rarely seen, yet despite receiving more than $1,900 a tonne, some producers plan either to cease or cut back production. Indeed, the high price was not enough to stop the world’s largest supplier warning this summer that profits would fall short of expectations.

The reasons why companies are not benefiting as much as they would like from the high metal price are soaring energy costs and the stubbornly high prices of alumina, the feedstock used to make aluminium.