mirabilite

{{Infobox mineral | name = Mirabilite | category = Sulfate minerals | boxwidth = | boxbgcolor = | image = Mangxiao.jpg | imagesize = 260px | caption = | formula = Na2SO4·10H2O | IMAsymbol = Mrb | molweight = 322.9 g/mol | strunz = 7.CD.10 | dana = | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = P21/c | color = Colorless, white, yellowish-white, greenish-white | habit = Granular or well-formed coarse crystals | lattice = | twinning = Interpenetration twinning on {001}; also on {100} | cleavage = {100} perfect, {001} poor, {010} poor | fracture = Conchoidal | tenacity = | mohs = 1.5–2 | luster = Vitreous | refractive = nα = 1.396, nβ = 1.4103, nγ = 1.419 | opticalprop = Biaxial (–), 2V=75.93° | birefringence = δ = 0.023 | pleochroism = none | streak = White | gravity = 1.49 | density = | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Transparent to translucent to opaque | other = Not radioactive, non-fluorescent | references = }}

Mirabilite, also known as Glauber's salt, is a hydrous sodium sulfate mineral with the chemical formula Na2SO4·10H2O. It is a vitreous, colorless to white monoclinic mineral that forms as an evaporite from sodium sulfate-bearing brines. It is found around saline springs and along saline playa lakes. Associated minerals include gypsum, halite, thenardite, trona, glauberite, and epsomite.