Sulfur contains both iron and sulfur. The amount of sulfur in  Ferro Sulphur might be between 28 and 32 and 48 or 50%. The quality of these ferro alloys is determined by their sulphur concentration. Ferro Sulphur is primarily used in metallurgy to provide steel or any other alloy with the requisite sulphur content. Since elemental sulphur has a low melting point and can accumulate on the surface of molten metal, releasing SO2, they are not utilized in elemental sulphur.