SHANGHAI, Sept. 5 (SMM) –In the spot market, copper offers were quoted between discounts of negative RMB 30/mt and premiums of positive RMB 80/mt today. Trade prices for standard-quality copper were between RMB 67,680-67880/mt in the morning business, and RMB 67,750-68,000/mt for high-quality copper. As SHFE copper prices moved lower after a low open, cargo-holders of spot copper tried to hold premiums. Market circulation was mainly high-quality copper. Price quotations were unstable due to turbulent market sentiments, resulting in poor market transactions.