Abstract:Smelting of copper and lead will produce a large number of slag, and its basic composition is based on the FeO-CaO-SiO2-Al2O3-MgO system. CaO-SiO2-Al2O3-MgO series low iron slag produced after selective recovery of iron can be used as raw materials for production of building materials such as glass-ceramics. Further understanding of physical and chemical properties of slag is beneficial to provide theoretical basis for its further comprehensive utilization. Chemical composition of a low iron smelting slag is analyzed. Viscosity and density of slag are measured by melt physical property tester. The results show that when slag basicity vibrates around 1, viscosity and density of slag appears severe vibration.