sarkinite

{{Infobox mineral | name = Sarkinite | category = Arsenate minerals | boxwidth = | boxbgcolor = | image = Sarkinit-24468.JPG | imagesize = 260px | caption = | formula = Mn2(AsO4)(OH) | IMAsymbol = Srk | molweight = | strunz = 8.BB.15 | dana = 41.6.3.3 | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = P2m | unit cell = a = 12.7795(13) Å b = 13.6127(14) Å c = 10.2188(11) Å β = 108.834(2)°; Z = 16 | color = Red to yellow | habit = Tabular or granular | twinning = | cleavage = Distinct on {100} | fracture = Irregular/Uneven, Conchoidal | tenacity = | mohs = 4–5 | luster = Greasy | polish = | refractive = nα=1.793, nβ=1.807, nγ=1.809 | opticalprop = Biaxial (−) | birefringence = δ = 0.016 | 2V = 83° (measured) | dispersion = r > v or r Z > Y | streak = Red to yellow | gravity = | density = 4.08 to 4.18 g/cm3 (measured) | melt = | fusibility = | diagnostic = | solubility = Readily soluble in dilute acids | diaphaneity = Semitransparent | other = | references = }} Sarkinite, synonymous with chondrarsenite and polyarsenite, is a mineral with formula Mn2(AsO4)(OH). The mineral is named for the Greek word σάρκιυος, meaning made of flesh, for its red color and greasy luster. The mineral was first noted in Sweden in 1865 as chondrarsenite, though not identified as sarkinite until 1885.

==Description== Sarkinite is red to yellow in color. It occurs as thick tabular crystals, short prismatic crystals, or has a granular habit. Sarkinite sometimes aggregates into a roughly spherical shape. Sarkinite is a member of the Wagnerite Group.