Specimen shows the structure characteristic of a high phosphorus content namely dendrites of pearlite, massive needles of iron carbide and fine ternary eutectic. The ternary eutectic contains ferrite particles sometimes with herring-bone formation set in a white matrix. The matrix is a mixture of iron carbide and iron phosphide. The alkaline sodium picrate etch will darken the carbide and Murakami's etch will have a similar effect on the phosphide.