hanksite

{{Infobox mineral | name = Hanksite | boxwidth = | boxbgcolor = | image = Hanksite-27109.jpg | imagesize = 260 | alt = | caption = Hanksite crystal from Searles Lake | category = Sulfate minerals, sulfate carbonate | formula = Na22K(SO4)9(CO3)2Cl | IMAsymbol = Hks | molweight = | strunz = 7.BD.30 | dana = | system = Hexagonal | class = Dipyramidal (6/m) H–M symbol: (6/m) | symmetry = P63/m | unit cell = a = 10.465(21) Å c = 21.191(43) Å; Z = 2 | color = Colorless to pale yellow, may be grayish green due to clay inclusions | colour = | habit = Occurs as short prismatic to tabular hexagonal crystals | twinning = | cleavage = Good on {0001} | fracture = Uneven | tenacity = Brittle | mohs = 3–3.5 | luster = Vitreous to dull | streak = White | diaphaneity = Transparent to translucent | gravity = 2.562 | density = | polish = | opticalprop = Uniaxial (−) | refractive = nω = 1.481, nε = 1.461 | birefringence = δ = 0.020 | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = Pale yellow under LW UV | absorption = | melt = | fusibility = | diagnostic = | solubility = Readily soluble in water | impurities = | alteration = | other = | prop1 = | prop1text = | references = }}

Hanksite is a sulfate mineral, distinguished as one of only a handful that contain both carbonate and sulfate ions (a sulfate carbonate). It has the chemical formula Na22K(SO4)9(CO3)2Cl.