Zinc inventories in China increased over the weekend. SMM data showed that social inventories of refined zinc ingots across Shanghai, Tianjin, Guangdong, Jiangsu, Zhejiang, Shandong and Hebei expanded by 3,200 mt from last Friday December 25 to 146,200 mt as of Monday December 28. The stocks were down 7,800 mt from last Monday December 21.