järnsulfid

Järnsulfid, also known as iron sulfide, is a chemical compound with the formula FeS. It exists in various forms, most commonly as pyrite (FeS2), also known as fool's gold, and pyrrhotite (Fe1-xS). Pyrite is a pale brass-yellow mineral with a metallic luster and a cubic crystal structure. Pyrrhotite is a magnetic iron sulfide mineral that can vary in stoichiometry.

Pyrite is the most abundant sulfide mineral and is found in a wide range of geological environments, including igneous, metamorphic, and sedimentary rocks. It often forms cubic or pyritohedral crystals. Pyrrhotite is typically found in mafic and ultramafic igneous rocks and is also present in some metamorphic rocks.

Järnsulfid has numerous applications. Pyrite has historically been used as a source of sulfur dioxide for sulfuric acid production. It is also a minor ore of iron and is sometimes used in the production of pigments. In more recent times, pyrite has gained interest for its potential use in battery technology, particularly as a cathode material in lithium-ion batteries. Pyrrhotite is also a minor source of iron and is sometimes used in the production of sulfur.

Both pyrite and pyrrhotite can be found as fossils, where they have replaced organic material. This process, known as pyritization, can preserve delicate structures of ancient organisms. Järnsulfid can also be encountered in biological contexts, for instance, in the formation of siderophores, iron-chelating compounds produced by microorganisms. When exposed to air and moisture, iron sulfides can oxidize, forming iron sulfates and releasing sulfuric acid. This process is significant in acid mine drainage.