What Is the Chemical Formula for Ferrous Sulfide?

FeS is the chemical equation for ferrous sulfide, also known as iron (II) sulfide. It is an ionic compound consisting of one Fe2+ ion and one S2-ion.

Pyrite is the most common form of naturally occurring ferrous sulfide. The name "pyrite" comes from "pyr," the Greek word for fire, and was given to this mineral because striking it with some metals creates sparks. The characteristics of ferrous sulfide in the form of pyrite include:

  • Brassy yellow color with bright metallic luster
  • Frequently occurs with gold, so earning its nickname of "fool's gold"
  • Harder than most metallic minerals
  • Reacts with strong acids to form hydrogen sulfide
  • Smells like sulfur when in powdered form
  • Often forms cubical or octahedron-shaped crystals with striations on the faces

Uses of ferrous sulfide include:

  • Production of sulfuric acid
  • Resulphurization in the production of stainless steel
  • Generation of hydrogen sulfide gas