“Kansite” = Mackinawite, FeS

Abstract

Abstract “Kansite” is mackinawite, FeS. References to recent publications establishing this and correctly describing this important corrosion compound are given. Besides appearing as a corrosion product, it occurs naturally in tidal sediments, where hydrogen sulfide reacts with iron or iron compounds and in most high temperature copper and nickel ore deposits. It also has been synthesized in the laboratory. Mackinawite has been observed repeatedly for nearly a century, but until 1963 was generally confused with a similar-appearing but much rarer ore mineral, valleriite, CuFeS2, and was described under that name.