Base metals prices on the Shanghai Futures Exchange continued to slide during morning trading on Wednesday, following disappointing Chinese economic data that heightened concerns over slowing growth in the world’s second largest economy. Aluminium premiums in Rotterdam and the US Midwest were higher week on week on Tuesday but the spot main Japanese ports premium dipped because of the quiet trading conditions. The main union at Escondida copper mine has delayed a strike scheduled to begin on Tuesday and agreed to extend talks with mine owner BHP. Secondary aluminium alloy prices in the United States are holding steady on the back of tight ingot capacity, despite continued declines in raw material costs. The US physical copper market is marking time until an expected revival following the national Labor Day holiday on September 3. Imported cargoes are increasingly unattractive to Chinese chrome buyers while the yuan weakens and supply remains high.