leonite

{{Infobox mineral | name = Leonite | image = Leonite-Halite-112539.jpg | alt = leonite as white pseudomorphs after sharp freestanding picromerite crystals sizes to 2 cm, perched on a matrix of crystallized halite. 5.5 × 4.7 × 3.4 cm | caption = Leonite | category = Sulfate mineral | formula = K2Mg(SO4)2·4H2O | IMAsymbol = Leo | molweight = 366.69 g/mol | strunz = 7.CC.55 | dana = 29.03.03.01 | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = C2/m | unit cell = a = 11.78, b = 9.53 c = 9.88 [Å]; β = 95.4°; Z = 4 | color = White to colorless, yellow | colour = | habit = Tabular crystals | twinning = {100} | cleavage = none | fracture = conchoidal | tenacity = | mohs = 2.5–3 | luster = Vitreous or waxy | streak = White | diaphaneity = Transparent to translucent | gravity = 2.201 | density = | polish = | opticalprop = Biaxial (+) | refractive = nα = 1.479 nβ = 1.482 nγ = 1.487 | birefringence = δ = 0.008 | pleochroism = | 2V = Measured: 90° Calc: 76° | dispersion = none | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = easy | diagnostic = | solubility = | impurities = | alteration = | other = Leonit, 钾镁矾, Leonita, Леонит, Kalium-Astrakanit, Kalium-Blödit | references = }}

Leonite is a hydrated double sulfate of magnesium and potassium. It has the formula K2SO4·MgSO4·4H2O. The mineral was named after Leo Strippelmann, who was director of the salt works at Westeregeln in Germany. The mineral is part of the blodite group of hydrated double sulfate minerals.