SHANGHAI, May 7 (SMM) – Spot copper premiums were quoted between positive RMB 60-100/mt in Shanghai in the morning business. Traded prices for standard-quality copper were between RMB 57,700-57,760/mt, and RMB 57,730-57,800/mt for high-quality copper. SHFE copper prices retreated by more than RMB 500/mt, but increases in spot copper premiums were limited. Cargo-holders showed unwillingness in moving goods at lower price levels, and cargo-holders of standard-quality copper especially held price quotes firm. Thus, its price difference with high-quality copper was only between RMB 10-20/mt. Supply of low-end hydro-copper was limited. Trader buying interest was restricted owing to marginal profit margins, while downstream producers stayed on the sidelines as copper prices fell. Market activity was lackluster as a consequence.