SHANGHAI, Oct. 18 (SMM) –Most scrap copper smelters surveyed kept raw material inventories low as sourcing on the domestic spot market has become difficult. The inversion in the price relationship between scrap and refined copper has forced smelters to cut scrap copper purchases. Large smelters were still able to purchase scrap copper in the market by passing some of their costs downstream. SMEs, on the other hand, have had to resort to consuming existing inventories. SMM expects that input inventory levels across the sample of scrap copper smelters surveyed to fall further.