Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO4)3− anion group and, more rarely, other arsenates with anions like AsO3(OH)2− (also written HAsO42−) (example: pharmacolite Ca(AsO3OH).2H2O) or (very rarely) [AsO2(OH)2]− (example: andyrobertsite). Arsenite minerals are much less common. Both the Dana and the Strunz mineral classifications place the arsenates in with the phosphate minerals. Example arsenate minerals include: Annabergite Ni3(AsO4)2·8H2O Austinite CaZn(AsO4)(OH) Clinoclase Cu3(AsO4)(OH)3 Conichalcite CaCu(AsO4)(OH) Cornubite Cu5(AsO4)2(OH)4 Cornwallite Cu2+5(AsO4)2(OH)2 Erythrite Co3(AsO4)2·8H2O Mimetite Pb5(AsO4)3Cl Olivenite Cu2(AsO4)OH Nickel–Strunz Classification -08- Phosphates IMA-CNMNC proposes a new hierarchical scheme (Mills et al., 2009). This list uses it to modify the Classification of Nickel–Strunz (mindat.org, 10 ed, pending publication). Abbreviations: "*" - discredited (IMA/CNMNC status). "?" - questionable/doubtful (IMA/CNMNC status). "REE" - Rare-earth element (Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) "PGE" - Platinum-group element (Ru, Rh, Pd, Os, Ir, Pt) 03.C Aluminofluorides, 06 Borates, 08 Vanadates (04.H V[5,6] Vanadates), 09 Silicates: Neso: insular (from Greek νησος nēsos, island) Soro: grouping (from Greek σωροῦ sōros, heap, mound (especially of corn)) Cyclo: ring Ino: chain (from Greek ις [genitive: ινος inos], fibre) Phyllo: sheet (from Greek φύλλον phyllon, leaf) Tekto: three-dimensional framework Nickel–Strunz code scheme: NN.XY.##x NN: Nickel–Strunz mineral class number X: Nickel–Strunz mineral division letter Y: Nickel–Strunz mineral family letter ##x: Nickel–Strunz mineral/group number, x add-on letter Class: arsenates and vanadates 08.A Arsenates and vanadates without additional anions, without H2O 08.AA With small cations (some also with larger ones): 05 Alarsite 08.AB With medium-sized cations: 25 Xanthiosite, 30 Lammerite, 35 Mcbirneyite, 35 Stranskiite, 35 Pseudolyonsite, 40 Lyonsite 08.AC With medium-sized and large cations: 05 Howardevansite; 10 Arseniopleite, 10 Caryinite, 10 Johillerite, 10 Nickenichite, 10 Bradaczekite, 10 Yazganite, 10 Odanielite; 25 Berzeliite, 25 Manganberzeliite, 25 Palenzonaite, 25 Schäferite; 75 Ronneburgite, 80 Tillmannsite, 85 Filatovite 08.AD With only large cations: 10 Weilite, 10 Svenekite; 30 Schultenite, 35 Chernovite-(Y), 35 Dreyerite, 35 Wakefieldite-(La), 35 Wakefieldite-(Nd), 35 Wakefieldite-(Ce), 35 Wakefieldite-(Y); 40 Pucherite, 50 Gasparite-(Ce), 50 Rooseveltite; 55 Tetrarooseveltite, 60 Chursinite, 65 Clinobisvanite 08.B Arsenates and vanadates with additional anions, without H2O 08.BA With small and medium-sized cations: 10 Bergslagite 08.BB With only medium-sized cations, (OH, etc.):RO4 £1:1: 15 Sarkinite; 30 Zincolivenite, 30 Eveite, 30 Olivenite, 30 Adamite, 30 Auriacusite; 35 Paradamite, 40 Wilhelmkleinite, 50 Namibite, 60 Urusovite, 65 Theoparacelsite, 70 Turanite, 75 Stoiberite, 80 Fingerite, 85 Averievite 08.BC With only medium-sized cations, (OH, etc.):RO4 >