Kipushi will have an average grade of 36.4% zinc over the first five years of production.

Sibanye’s Beatrix, Driefontein and Kloof mines employ about 31,000 workers.

If the shareholders tender their shares, then it would end several months of tussle between Impala and its rival Northam Platinum.

"There's a general cooling of the economy in China. Infrastructure and property are both key in terms of driving metals demand and we do not expect a quick reversal in either."

Barrick says its geological improvements and remodelling are starting to make a positive impact.