augelite

{{Infobox mineral | name = Augelite | boxwidth = | boxbgcolor = | image = Augelite-78938.jpg | imagesize = 260px | alt = | caption = | category = Phosphate mineral | formula = Al2(PO4)(OH)3 |IMAsymbol=Aul | molweight = | strunz = 8.BE.05 | dana = | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = C2/m | unit cell = a = 13.124(6), b = 7.988(5) c = 5.0633(3) [Å] β = 112.25(2)°; Z = 4 | color = Colorless to white, may be yellowish to pale rose, greenish | habit = Tabular to prismatic or acicular crystals; massive | twinning = | cleavage = Perfect on {110}, good on {201}, imperfect on {001} and {101} | fracture = Uneven | tenacity = Brittle | mohs = 4 – 4.5 | luster = Vitreous, pearly on {110} cleavage | streak = White | diaphaneity = Transparent | gravity = 2.696 | density = | polish = | opticalprop = Biaxial (+) | refractive = nα = 1.574 nβ = 1.576 nγ = 1.588 | birefringence = δ = 0.014 | pleochroism = | 2V = Measured: 50° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = }} Augelite is an aluminium phosphate mineral with formula: Al2(PO4)(OH)3. The shade varies from colorless to white, yellow or rose. Its crystal system is monoclinic.

It was first described by Christian Wilhelm Blomstrand for an occurrence in Västanå iron mine at Scania, Sweden in 1868 and derives its name from the Greek αύγή in reference to its pearly lustre.