SHANGHAI, Apr. 1 (SMM) – Spot copper premiums RMB 100-220/mt in Shanghai on Monday. Traded prices for standard-quality copper were between RMB 54,380-54,480/mt, and RMB 54,460-54,570/mt for high-quality copper. The most active SHFE copper contract tumbled by RMB 1,000/mt, leading to a sharp increase in spot copper premiums. Downstream producers and middlemen were active in bargain hunting, allowing cargo holders to hold offers firm. The price spread between standard-quality copper and high-quality copper narrowed and trading was brisk.