eosphorite

{{Infobox mineral | name = Eosphorite | boxwidth = | boxbgcolor = | image = Éosphorite, quartz.jpeg | alt = | caption = | category = Phosphate mineral | formula = MnAl(PO4)(OH)2·H2O | IMAsymbol = Eos | molweight = | strunz = 8.DD.20 | dana = | system = Orthorhombic | class = Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) | symmetry = Cmca | unit cell = a = 10.455(1), b = 13.501(2) c = 6.928(1) [Å]; β = 90°; Z = 8 | color = usually pale brown, golden brown, also medium brown to dark brown; occasionally pink, rose red | colour = | habit = Prismatic in radiating sprays or spheres, massive; twinned pseudo-orthorhombic | twinning = May be observed on {100} and {001} | cleavage = Poor on {100} | fracture = Subconchoidal to uneven | tenacity = | mohs = 5 | luster = Vitreous, resinous | streak = White | diaphaneity = Transparent to translucent | gravity = 3.06 – 3.08 | density = | polish = | opticalprop = Biaxial (-) | refractive = nα = 1.628 - 1.639 nβ = 1.648 - 1.664 nγ = 1.657 - 1.671 | birefringence = δ = 0.029 - 0.032 | pleochroism = Visible: X = yellow; Y = pink; Z = pale pink to colorless | 2V = Measured: 50° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = Oxidizes to brown or black | other = | prop1 = | prop1text = | references = }}

Eosphorite is a brown (occasionally pink) manganese hydrous phosphate mineral with chemical formula: MnAl(PO4)(OH)2·H2O. It is used as a gemstone.