legrandite

{{Infobox mineral | name = Legrandite | category = Arsenate minerals | boxwidth = | boxbgcolor = | image = Legrandite, limonite 1100.1.2839.jpg | imagesize = 260px | caption = | formula = Zn2(AsO4)(OH)·(H2O) | IMAsymbol = Leg | strunz = 8.DC.10 | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = P21/c | unit cell = a = 12.805(2), b = 7.933(1) c = 10.215(2) [Å]; β = 104.23°; Z = 8 | color = Bright yellow, wax-yellow, colorless | habit = Crystalline, prismatic, typically in sprays or sheaflike aggregates | twinning = | cleavage = Imperfect, poor one {100} | fracture = Conchoidal | tenacity = Brittle | mohs = 4.5–5 | luster = Vitreous | refractive = nα = 1.675 – 1.702 nβ = 1.690 – 1.709 nγ = 1.735 – 1.740 | opticalprop = Biaxial (+) | birefringence = δ = 0.060 | pleochroism = X = Y = Colorless to yellow Z = Yellow | 2V = Measured: 50° | streak = White | gravity = 3.98–4.01 | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Transparent to translucent | other = | references = }}

Legrandite is a rare zinc arsenate mineral, Zn2(AsO4)(OH)·(H2O).