SHANGHAI, May 11 (SMM) – Offers for spot copper premiums were between positive RMB 20-80/mt in Shanghai in the morning business. Traded prices for standard-quality copper were between RMB 57,720-57,820/mt, and RMB 57,750-57,880/mt for high-quality copper. SHFE copper prices were volatile, but spot copper supply remained stable. Spot copper premiums fell gradually. Cargo-holders held divergent views towards volatile copper prices, while downstream producers were still wary of purchases, keeping market activity modest.