Sulfides of many important metallic elements are naturally occurring minerals. For example, pyrite, which is also called fool's gold owing to its brassy yellow colour, is a sulfide of iron with the formula FeS₂. Pyrite is a major source of iron and is one of the most abundant of the sulfur minerals. zinc, cadmium, mercury, copper, silver, and many other elements occur in nature as sulfides.

The alkali metals (alkali metal) and alkaline-earth metals (alkaline-earth metal) are the only sulfides that have any appreciable water solubility and that appear to be primarily ionic. In contrast, the sulfides of the copper and zinc families are some of the least-soluble compounds known. When water-soluble metal sulfides are heated in aqueous solution with elemental sulfur, solutions of so-called polysulfides are formed. These solutions consist primarily of S₄²⁻ and S₃²⁻ anions (anion). Sulfides are an important component of high-density power sources such as lithium and sodium sulfide batteries (battery). The sulfides that have been utilized in these power sources are M₂S, M₂S₂, M₂S₄, and M₂S₅.

Semimetals (metalloids) and some nonmetallic elements form sulfides that are molecular or that have sulfide bridges in a polymeric structure. For example, silicon disulfide, SiS₂, has a structure consisting of infinite chains of SiS₄ tetrahedrons that share edges. (Each SiS₄ tetrahedron consists of a central silicon atom surrounded by and bonded to four sulfur atoms.) phosphorus forms a series of molecular sulfides that includes P₄S₃, P₄S₄ (two distinct forms), P₄S₅, P₄S₇, P₄S₉, and P₄S₁₀. The structures of all these compounds are derived from a P₄ tetrahedron in which P−P bonds are replaced by P−S−P units. All these phosphorus sulfides are stable in carbon disulfide (CS₂), and all react with water to produce phosphoric acid (H₃PO₄) or other phosphorus oxyacids (oxyacid).