Copper has slid 14% from this year’s high in mid-April on the back of a manufacturing slump and warnings that major economies are heading into recession.

Africa's No. 2 copper producer increased its sliding scale for royalties of 4 to 6% by 1.5 percentage points and introduced a new 10% tax when the price of copper exceeds $7,500 per tonne.

Australia's tax office ruled the company had paid the correct amount of tax on purchases of copper concentrate from a New South Wales mine.

But further developments in aluminium technology could lead to increased substitution of copper in cabling.

A regional ordinance states that the Freeport-McMoRan operation would only expand onto wasteland.

Global Energy Metals struck an option agreement in January with Nevada Sunrise Gold to acquire 85% of the historic Lovelock cobalt mine and nearby Treasure Box properties.

At some point it won’t make sense anymore to dig for raw materials, because enough batteries are available.

The partners are looking for a "suitable piece of land" for the project.