Cohenite - iron carbide Chromite - iron magnesium chromium oxide Daubréelite - iron(II) chromium sulfide Diamond and lonsdaleite - carbon Graphite - carbon Haxonite - iron nickel carbide Kamacite iron nickel alloy - the most common component. Base metal sulfides Schreibersite - iron nickel phosphide Taenite - iron nickel alloy Troilite - a variety of the iron sulfide mineral pyrrhotite. The troilite in this sample is used as the standard reference for sulfur isotope ratios.