The mineral vanackerite (IMA 2011-114), Pb4Cd(AsO4)(3)Cl is a new member of the apatite supergroup of minerals and a Cd-substituted derivative of mimetite. Vanackerite is trigonal with space group P (3) over bar and its crystal structure is obtained from the hexagonal mimetite structure by site-splitting of one of the Pb-positions, accompanied by rotation of the arsenate tetrahedra. Single crystal X-ray diffraction yields a = 10.0279(3) angstrom, c =7.2965(2) angstrom, V=635.43(4) angstrom(3) and Z=2. The strongest X-ray powder reflections are as follows, d(obs). (angstrom) (I; hkl): 2.982 (100; 211,112, 300), 3.290 (34; 102, 3 (2) over bar0), 2.067 (16; 222) and 1.944 (11; 3 (1) over bar3). Chemical analyses gave (wt.%): Pb0 64.44, CdO 8.82, As2O5 23.59, C11.51, O Cl-0.34, sum 98.02 wt.%. The resulting empirical formula based on 8 cations pfu is Pb4.10Cd0.98As292O12.07Cl0.61.The new mineral was collected in 1980 and since then mistaken for mimetite. The sample originates from the second oxidation zone of the Tsumeb ore deposit, Tsumeb, Namibia. Vanackerite occurs as light yellow rosettes of thin pseudohexagonal tabular crystals up to 5 mm in size on bluish green thometzekite, further associated minerals are anglesite and gypsum. Its calculated density is 7.28, the calculated mean refractive index is 2.04.

The new mineral erikapohlite (IMA-CNMNC No. 2010-090) has the chemical formula Cu-3(Zn,Cu,Mg)(4)Ca-2(AsO4)(6)center dot 2H(2)O. It is the Ca-dominant analogue of keyite, Cu-3(Zn,Cu,Mg)(4)Cd-2(AsO4)(6)center dot 2H(2)O. Erikapohlite is metrically monoclinic with space group C2/c. X-ray powder diffraction studies gave a = 12.6564(6) angstrom, b = 12.7282(8) angstrom, c = 6.9148(3) angstrom and beta = 113.939(4)degrees, V = 1018.11(6) angstrom(3), Z = 2. The strongest refl ections in the X-ray powder diffraction data are as follows d(obs). (angstrom) (I, hkl): 2.8919 (100, 400), 3.3043 (49, 11 (2) over bar), 2.7880 (40, 240), 3.1600 (32, 002) and 2.7638 (14, 40 (2) over bar). Chemical analyses gave (wt.%): CuO 22.42, ZnO 14.45, CaO 8.21, MgO 2.21, FeO 0.03, As2O5 51.02, H2O(by difference) 1.66, sum 100.00 wt.%. The resulting empirical formula based on 26 anions is Cu-3(Zn2.48Cu0.93Mg0.77Fe0.01)(Sigma 4.19)Ca2.04As6.20O24.71 center dot 1.29H(2)O. Small zones in erikapohlite are Mg-or Cu-dominant, thus representing new mineral species, which still have to be characterized.

The new mineral hermannroseite (IMA-CNMNC No. 2010-006) has the chemical formula CaCu(PO4,AsO4)(OH). It is the phosphate analogue of conichalcite, CaCu(AsO4)(OH) and belongs to the adelite group where it represents the first phosphate end-member of this group. Hermannroseite is orthorhombic with space group P2(1)2(1)2(1). X-ray powder diffraction studies gave a: 7.328(7), b: 9.123(7), c: 5.769(6) angstrom, V = 385.7(6) angstrom(3) , Z = 4. The strongest reflections in the X-ray powder diffraction data are as follows d(obs). (angstrom) (I, hkl): 2.808 (100, 130), 2.571 (73, 112), 3.092 (63, 201), 5.710 (56, 110) and 4.057 (37, 111). Hermannroseite was found in the Tsumeb mine, Tsumeb, Namibia. With a mean grain size of 0.7 mu m hermannroseite occurs within botryoidal agge-gates and crusts of micro crystalline conichalcite in association with hydroxylapatite, whitlockite, pseudomalachite and amorphous manganese oxides/hydroxides.Hermannroseite is translucent with a vitreous green colour. The calculated density is 4.08 g/cm(3), the calculated mean refractive index is 1.77. Chemical analyses gave (wt.%): CaO 22.80, CuO 34.52, ZnO 0.58, P2O5 15.16, As2O5 21.88, V2O5 1.02, H2O(by difference) 4.04, sum 100.00 wt.%. The resulting empirical formula based on 5 anions is Ca-0.96(Cu1.03Zn0.02)(P(0.51)AS(0.45)V(0.03)) O-3.94(OH)(1.06).