English: A micrograph of a section of carburized steel. The magnification is 200x. According to the scouse of this photograph, the original steel is a low carbon steel including 0.2% C, 0.24% Si, 0.52% Mn, 0.46% Ni, and 0.17%Cr. The black portions of the photograph is pearlite that was made by carburizing. The white portions are ferrite. Being exposed to the mixture of 70% charcoal and 30% barium carbonate, the steel was kept at 930 degrees C, then was cooled in furnace.