pyrite

{{Infobox mineral | name = Pyrite | category = Sulfide mineral | boxbgcolor = | image = Pyrite - Huanzala mine, Huallanca, Bolognesi, Ancash, Peru.jpg | imagesize = 260px | caption = Intergrowth of lustrous, cubic crystals of pyrite, with some surfaces showing characteristic striations, from Huanzala mine, Ancash, Peru. Specimen size: 7.0 × 5.0 × 2.5 cm | formula = FeS2 | IMAsymbol = Py | molweight = 119.98 g/mol | strunz = 2.EB.05a | dana = 2.12.1.1 | system = Cubic | class = Diploidal (m) H-M symbol: (2/m ) | symmetry = Pa | unit cell = a = 5.417 Å, Z = 4 | color = Pale brass-yellow reflective; tarnishes darker and iridescent | habit = Cubic, faces may be striated, but also frequently octahedral and pyritohedral. Often inter-grown, massive, radiated, granular, globular, and stalactitic. | twinning = Penetration and contact twinning | cleavage = Indistinct on {001}; partings on {011} and {111} | fracture = Very uneven, sometimes conchoidal | tenacity = Brittle | mohs = 6–6.5 | luster = Metallic, glistening | refractive = | opticalprop = | birefringence = | pleochroism = | streak = Greenish-black to brownish-black | gravity = 4.95–5.10 | density = | melt = | fusibility = 2.5–3 to a magnetic globule | diagnostic = | solubility = Insoluble in water | diaphaneity = Opaque | other = Diamagnetic to paramagnetic A semiconductor with bandgap of 0.72 to 3.26 eV. | references = }}

The mineral pyrite ( ), or iron pyrite, also known as '''Fool's Gold''', is an iron sulfide with the chemical formula FeS2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.