BEIJING: China's major copper smelters reduced output in July by 7.2pc year-on-year due to summer maintenance, while zinc output rose, research house Antaike said on Monday.

Its survey of 22 copper smelters put refined cathode output at 687,100 tonnes last month, down 1.7pc from a revised 699,200 tonnes for June.

The main factors behind the drop were maintenance at Jinchuan Group's 400,000 tonnes per year smelter in Guangxi and the relocation of a smelter in Inner Mongolia, Antaike said.

Maintenance will be lower in August but treatment charges at "a relatively low historical level" of around $50 a tonne will limit production to around 710,000 tonnes this month, it added.

Separately, zinc output from 49 Chinese producers surveyed by Antaike came in at 430,000 tonnes in July, up 0.2pc year-on-year and up 6.7pc from June as smelters in Inner Mongolia, Yunnan, Anhui came back from maintenance.

Zinc ingot inventories at most smelters and factories are already at zero or low levels as demand recovers, said Antaike, which sees August zinc output rising by around 6,000 tonnes, followed by a further increase in September.