Iron(II) sulfide is used as a pigment in hair dyes and ceramics, glasses and bottles, and paint, Also used in lubricants and anodes, as a hydrogen sulfide source, and to treat exhaust gases. It is also used as resulphurising agent in the production of carbon, alloy and stainless types of free cutting steels. It acts as an alloying agent to improve machine ability of steel castings which are used to manufacture various steel components.