SMM, April 29: today's North China electrolytic copper spot contract for the current month, water 190 yuan / ton ~ 250 yuan / ton, transaction price 42790 yuan / ton ~ 42980 yuan / ton. Shanghai copper low open high moved up to 42700 yuan / ton. Tianjin large downstream factory stock is sufficient, a small number of downstream sporadic replenishment; Shanghai shipped to Tianjin wet method and fire method supply has increased significantly, the supply is now abundant, Gaoshengshui is willing to buy weak, local traders take the initiative to lower the spot quotation again, the current offer is around 200 yuan / ton, the average price is 40 yuan / ton lower than yesterday.