SHANGHAI, Jan. 28 (SMM) – On January 28, spot copper was offered at discounts of RMB 150-450/mt against SHFE 1402 copper contract prices in Shanghai. Standard-quality copper was traded at RMB 50,620-50,720/mt and high-quality copper was sold at RMB 50,800-50,880/mt. As most enterprises started holiday, copper supply declined in spot markets, and most goods available in the market were hydro-copper and standard-quality copper. Holders of high-grade copper held prices up and refrained from selling, leaving price gap between high-quality and standard-quality copper at RMB 300/mt. However, transactions were rarely made.