The quantitative structural information such as the relative abundance of silicate discrete anions (Qⁿ units) and the concentration of three types of oxygens, viz. free–, bridging– and nonbridging oxygen can be obtained from micro–Raman spectra of the quenched CaO–SiO₂–MnO glass samples. Various transport properties such as viscosity, density, and electrical conductivity can be expected as a simple linear function of ‘ln (Q³/Q²),’ indicating that these thermophysical properties are strongly dependent on a degree of polymerization of silicate melts in the composition of silica content greater than about 30 mol%. The present methodology is believed to be widely extended to various slag systems in ferrous and non–ferrous metallurgical communities.