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Agardite-(Ce) from Clara Mine, Schwarzwald, Germany, has been investigated by means of electron microprobe analysis, single-crystal X-ray analysis, XANES spectroscopy and IR spectroscopy. Hexagonal unit-cell parameters are: a = 13.598(6), c = 5.954(3) A; V = 953.5(2) A3; space group P63/m. The structure has been solved and refined to final R 1 = 3.87%, wR 2 = 5.02 for 786 I > 3σ(I). Hydrogen atoms have been localized. The crystal-chemical formula is (Z = 2): A(1)(Ce0.82Ca0.14Sr0.04)Σ1.00 A(2)(Ca0.03Ce0.02)Σ0.05 [Cu5.75(Fe3+, Mn)0.20]Σ5.95 [ T(1)(AsO4) 2.96 (2) (SbO4)0.04)]Σ3.00 (OH)5.96O0.04·3H2O. Hydrogen bonding in agardite-series minerals has been characterized for the first time. IR spectra of agardite-(Ce) and agardite-(Nd) from Lavrion used for comparison, as well as structural data indicate the presence of isolated H+ cations that do not form strong covalent bonds with coordinating O atoms. Agardite-(Ce) from Clara Mine forms epitaxial growths with the Sb-analogue of auriacusite. The latter mineral was characterized by EDS analyses; its typical empirical formulae are $${\text{Ca}}_{0.0 6} {\text{Ce}}_{0.0 4} {\text{Fe}}^{ 3+ }{}_{ 1.0 6} {\text{Cu}}_{0. 8 9}$$ [(SbO4)0.58(AsO4)0.38(SiO4)0.04]Σ1.00(O,OH) and $${\text{Ca}}_{0.0 7 5} {\text{Ce}}_{0.0 4} {\text{Fe}}^{ 3+ }{}_{0. 9 3} {\text{Cu}}_{0. 9 7}$$ [(SbO4)0.59(AsO4)0.35(SiO4)0.06]Σ1.00(O,OH). The formation of uniaxial growths of the Sb-analogue of auriacusite and agardite-(Ce) is caused by the close values of their c parameters (for auriacusite s.s. c = 5.9501(5) A). Three-valence state of iron and five-valence of antimony in both minerals has been validated by means of Fe K- and Sb L 2,3-edge XANES spectroscopy.

The new ettringite-group mineral kottenheimite was found at Bellerberg, near Kottenheim, Eastern Eifel area, Rhineland- Palatinate (Rheinland-Pfalz), Germany, and named for the type locality. Associated minerals are wollastonite, clinochlore, ellestadite, melilite, cuspidine, and earlier formed sanidine, clinopyroxene, and magnetite. Kottenheimite forms white radiated and random aggregates of hair-like subparallel clusters of minute crystals. The Mohs’ hardness is 2–2.5; D meas = 1.92(2) g/cm 3 , D calc = 1.926 g/cm 3 . The new mineral is uniaxial (−), ω = 1.490(2), ɛ = 1.477(2). The IR spectrum of kottenheimite is in accordance with the chemical composition and contains absorption bands in the range 3300–3700 cm −1 (O–H-stretching vibrations), at 1650 and 1683 cm −1 (bending vibrations of H 2 O molecules), 1158, 1086, and 987 cm −1 (showing the presence of distorted SO 4 2− groups), 752 and 725 cm −1 (corresponding to Si–O stretching vibrations of Si(OH) 6 octahedra). The chemical composition is (electron microprobe, mean of 6 analyses, wt.%; H 2 O and CO 2 determined by gas chromatography): CaO 26.04, MgO 0.20, FeO 0.19, Al 2 O 3 0.25, SiO 2 8.95, SO 3 24.26, CO 2 0.58, H 2 O 41.30; total 101.77. The empirical formula calculated on the basis of 26 anions is Ca 3.015 Mg 0.03 Fe 0.02 Al 0.03 Si 0.97 (OH) 5.94 (SO 4 ) 1.97 (CO 3 ) 0.09 ·11.91H 2 O. The simplified formula is Ca 3 Si(OH) 6 (SO 4 ) 2 ·12H 2 O. The crystal structure was refined by the Rietveld method ( R p = 0.0487, R wp = 0.0623, R B = 0.087) based on the structural model of carraraite, Ca 3 Ge(SO 4 ,CO 3 ) 2 (OH) 6 ·12H 2 O. The new mineral is hexagonal, space group P 6 3 / m , a = 11.1548(3), c = 10.5702(3) A, V = 1139.04(5) A 3 , and Z = 2. The strongest lines of the powder diffraction pattern [ d in A ( I ) ( hkl )] are: 9.72 (100) (100), 5.590 (60) (110), 4.645 (26) (102), 3.840 (54) (112), 2.751 (34) (302), 2.536 (27) (213), 2.185 (30) (223). The channels in the crystal structure of kottenheimite are only filled by sulfate anions and water molecules. Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, registration number 4102/1.

Oxyphlogopite is a new mica-group mineral with the idealized formula K(Mg,Ti,Fe)3[(Si,Al)4O10](O,F)2. The holotype material came from a basalt quarry at Mount Rothenberg near Mendig at the Eifel volcanic complex in Rhineland-Palatinate, Germany. The mineral occurs as crystals up to 4 × 4 × 0.2 mm in size encrusting cavity walls in alkali basalt. The associated minerals are nepheline, plagioclase, sanidine, augite, diopside, and magnetite. Its color is dark brown, its streak is brown, and its luster is vitreous. Dmeas = 3.06(1) g/cm3 (flotation in heavy liquids), and Dcalc = 3.086 g/cm3. The IR spectrun does not contain bands of OH groups. Oxyphlogopite is biaxial (negative); α = 1.625(3), β = 1.668(1), and γ = 1.669(1); and 2Vmeas = 16(2)° and 2Vcalc = 17°. The dispersion is strong; r Y > Z (brown to dark brown). The chemical composition is as follows (electron microprobe, mean of 5 point analyses, wt %; the ranges are given in parentheses; the H2O was determined using the Alimarin method; the Fe2+/Fe3+ was determined with X-ray emission spectroscopy): Na2O 0.99 (0.89–1.12), K2O 7.52 (7.44–7.58), MgO 14.65 (14.48–14.80), CaO 0.27 ((0.17–0.51), FeO 4.73, Fe2O3 7.25 (the range of the total iron in the form of FeO is 11.09–11.38), Al2O3 14.32 (14.06–14.64), Cr2O3 0.60 (0.45–0.69), SiO2 34.41 (34.03–34.66), TiO2 12.93 (12.69–13.13), F 3.06 (2.59–3.44), H2O 0.14; O=F2 −1.29; 99/58 in total. The empirical formula is (K0.72Na0.14Ca0.02)(Mg1.64Ti0.73Fe0.302+ Fe0.273+Cr0.04)Σ2.98(Si2.59Al1.27Fe0.143+ O10) O1.20F0.73(OH)0.07. The crystal structure was refined on a single crystal. Oxyphlogopite is monoclinic with space group C2/m; the unit-cell parameters are as follows: a = 5.3165(1), b = 9.2000(2), c = 10.0602(2) A, β = 100.354(2)°. The presence of Ti results in the strong distortion of octahedron M(2). The strongest lines of the X-ray powder diffraction pattern [d, A (I, %) [hkl]] are as follows: 9.91(32) [001], 4.53(11) 110], 3.300(100) [003], 3.090(12) [112], 1.895(21) [005], 1.659(12) [−135], 1.527(16) [−206, 060]. The type specimens of oxyphlogopite are deposited at the Fersman Mineralogical Museum in Moscow, Russia; the registration numbers are 3884/2 (holotype) and 3884/1 (cotype).

Nickeltalmessite, Ca2Ni(AsO4)2 · 2H2O, a new mineral species of the fairfieldite group, has been found in association with annabergite, nickelaustinite, pecoraite, calcite, and a mineral of the chromite-manganochromite series from the dump of the Ait Ahmane Mine, Bou Azzer ore district, Morocco. The new mineral occurs as spheroidal aggregates consisting of split crystals up to 10 × 10 × 20 μm in size. Nickeltalmessite is apple green, with white streak and vitreous luster. The density measured by the volumetric method is 3.72(3) g/cm3; calculated density is 3.74 g/cm3. The new mineral is colorless under a microscope, biaxial, positive: α = 1.715(3), β = 1.720(5), γ = 1.753(3), 2Vmeas = 80(10)°, 2Vcalc = 60.4. Dispersion is not observed. The infrared spectrum is given. As a result of heating of the mineral in vacuum from 24° up to 500°C, weight loss was 8.03 wt %. The chemical composition (electron microprobe, wt %) is as follows: 25.92 CaO, 1.23 MgO, 1.08 CoO, 13.01 NiO, 52.09 As2O5; 7.8 H2O (determined by the Penfield method); the total is 101.13. The empirical formula calculated on the basis of two AsO4 groups is Ca2.04(Ni0.77Mg0.13Co0.06)Σ0.96 (AsO4)2.00 · 1.91H2O. The strongest reflections in the X-ray powder diffraction pattern [d, A (I, %) (hkl)] are: 5.05 (27) (001) (100), 3.57 (43) (011), 3.358 (58) (110), 3.202 (100) (020), 3.099 (64) (0\( \bar 2 \)1), 2.813 (60), (\( \bar 1 \)21), 2.772 (68) (2\( \bar 1 \)0), 1.714 (39) (\( \bar 3 \)31). The unit-cell dimensions of the triclinic lattice (space group P1 or P) determined from the X-ray powder data are: a = 5.858(7), b = 7.082(12), c = 5.567(6) A, α = 97.20(4), β = 109.11(5), γ = 109.78(5)°, V = 198.04 A3, Z = 1. The mineral name emphasizes its chemical composition as a Ni-dominant analogue of talmessite. The type material of nickeltalmessite is deposited at the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, Russia, registration number 3750/1.

Kamarizaite, a new mineral species, has been identified in the dump of the Kamariza Mine, Lavrion mining district, Attica Region, Greece, in association with goethite, scorodite, and jarosite. It was named after type locality. Kamarizaite occurs as fine-grained monomineralic aggregates (up to 3 cm across) composed of platy crystals up to 1 μm in size and submicron kidney-shaped segregations. The new mineral is yellow to beige, with light yellow streak. The Mohs hardness is about 3. No cleavage is observed. The density measured by hydrostatic weighing is 3.16(1) g/cm3, and the calculated density is 3.12 g/cm3. The wavenumbers of absorption bands in the IR spectrum of kamarizaite are (cm−1; s is strong band, w is weak band): 3552, 3315s, 3115, 1650w, 1620w, 1089, 911s, 888s, 870, 835s, 808s, 614w, 540, 500, 478, 429. According to TG and IR data, complete dehydration and dehydroxylation in vacuum (with a weight loss of 15.3(1)%) occurs in the temperature range 110–420°C. Mossbauer data indicate that all iron in kamarizaite is octahedrally coordinated Fe3+. Kamarizaite is optically biaxial, positive: n min = 1.825, n max = 1.835, n mean = 1.83(1) (for a fine-grained aggregate). The chemical composition of kamarizaite (electron microprobe, average of four point analyses) is as follows, wt %: 0.35 CaO, 41.78 Fe2O3, 39.89 As2O5, 1.49 SO3, 15.3 H2O (from TG data); the total is 98.81. The empirical formula calculated on the basis of (AsO4,SO4)2 is Ca0.03Fe 2.86 3+ (AsO4)1.90(SO4)0.10(OH)2.74 · 3.27H2O. The idealized formula is Fe 3 3+ (AsO4)2(OH)3 · 3H2O. Kamarizaite is an arsenate analogue of orthorhombic tinticite, space group Pccm, Pcc2, Pcmm, Pcm21, or Pc2m; a = 21.32(1), b = 13.666(6), c =15.80(1) A, V= 4603.29(5) A3, Z= 16. The strongest reflections of the X-ray powder diffraction pattern [ $$ \bar d $$ , A (I, %) (hkl)] are: 6.61 (37) (112, 120), 5.85 (52) (311), 3.947 (100) (004, 032, 511), 3.396 (37) (133, 431), 3.332 (60) (314), 3.085 (58) (621, 414, 324). The type material of kamarizaite is deposited in the Mineralogical Collection of Technische Universitat Bergakademie Freiberg, Germany, inventory number 82199.

Bendadaite, ideally Fe2+Fe23+ (AsO4)2(OH)2·4H2O, is a new member of the arthurite group. It was found as a weathering product of arsenopyrite on a single hand specimen from the phosphate pegmatite Bendada, central Portugal (type locality). Co-type locality is the granite pegmatite of Lavra do Almerindo (Almerindo mine), Linópolis, Divino das Laranjeiras county, Minas Gerais, Brazil. Further localities are the Veta Negra mine, Copiapó province, Chile; Oumlil-East, Bou Azzer district, Morocco; and Pira Inferida yard, Fenugu Sibiri mine, Gonnosfanadiga, Medio Campidano Province, Sardinia, Italy.Type bendadaite occurs as blackish green to dark brownish tufts (P21/c, with a = 10.239(3) Å, b = 9.713(2) Å, c = 5.552(2) Å, β = 94.11(2)°, V = 550.7(2) Å3, Z = 2. Electron-microprobe analysis yielded (wt.%): CaO 0.04, MnO 0.03, CuO 0.06, ZnO 0.04, Fe2O3 (total) 43.92, Al2O3 1.15, SnO2 0.10, As2O5 43.27, P2O5 1.86, SO3 0.03. The empirical formula is (Fe2+0.52Fe3+0.32☐0.16)Σ1.00(Fe3+1.89Al0.11)Σ2.00(As1.87P0.13)Σ2.00O8(OH)2.00·4H2O based on 2(As,P) and assuming ideal 8O, 2(OH), 4H2O and complete occupancy of the ferric iron site by Fe3+ and Al. Optically, bendadaite is biaxial, positive, 2Vest. = 85±4°, 2Vcalc. = 88°, with α 1.734(3), β 1.759(3), γ 1.787(4). Pleochroism is medium strong: X pale reddish brown, Y yellowish brown, Z dark yellowish brown; absorption Z > Y > X, optical dispersion weak, r > v. Optical axis plane is parallel to (010), with X approximately parallel to a and Z nearly parallel to c. Bendadaite has vitreous to sub-adamantine luster, is translucent and non-fluorescent. It is brittle, shows irregular fracture and a good cleavage parallel to {010}. Dmeas. 3.15±0.10 g/cm3, Dcalc. 3.193 g/cm3 (for the empirical formula). The five strongest powder diffraction lines [d in Å (I)(hkl)] are 10.22 (10)(100), 7.036 (8)(110), 4.250 (5)(111), 2.865 (4)(), 4.833 (3)(020,011). The d spacings are very similar to those of its Zn analogue, ojuelaite. The crystal structure of bendadaite was solved and refined using a crystal from the co-type locality with the composition (Fe2+0.95☐0.05)Σ1.00(Fe3+1.80Al0.20)Σ2.00(As1.48P0.52)Σ2.00O8(OH)2·4H2O (R = 1.6%), and confirms an arthurite-type atomic arrangement.

Footemineite, ideally Ca 2 Mn 2+ □Mn 2 2+ Mn 2 2+ Be 4 (PO 4 ) 6 (OH) 4 ·6H 2 O, triclinic, is a new member of the roscherite group. It occurs on thin fractures crossing quartz-microcline-spodumene pegmatite at the Foote mine, Kings Mountain, Cleveland County, North Carolina, U.S.A. Associated minerals are albite, analcime, eosphorite, siderite/rhodochrosite, fairfieldite, fluorapatite, quartz, milarite, and pyrite. Footemineite forms prismatic to bladed generally rough to barrel-shaped crystals up to about 1.5 mm long and 1 mm in diameter. Its color is yellow, the streak is white, and the luster is vitreous to slightly pearly. Footemineite is transparent and non-fluorescent. Twinning is simple, by reflection, with twin boundaries across the length of the crystals. Cleavage is good on {011} and {100}. Density (calc.) is 2.873 g/cm 3 . Footemineite is biaxial (−), n α = 1.620(2), n β = 1.627(2), n γ = 1.634(2) (white light). 2 V obs = 80°, 2 V calc = 89.6°. Orientation: X ^ b ~ 12°, Y ^ c ~ 15°, Z ^ a ~ 15°. Elongation direction is c , dispersion: r > v or r α = γ (yellow). Mossbauer and IR spectra are given. The chemical composition is (EDS mode electron microprobe, Li and Be by ICP-OES, Fe 3+ : Fe 2+ by Mossbauer, H 2 O by TG data, wt%): Li 2 O 0.23, BeO 9.54, CaO 9.43, SrO 0.23, BaO 0.24, MgO 0.18, MnO 26.16, FeO 2.77, Fe 2 O 3 0.62, Al 2 O 3 0.14, P 2 O 5 36.58, SiO 2 0.42, H 2 O 13.1, total 99.64. The empirical formula is (Ca 1.89 Sr 0.03 Ba 0.02 ) ∑1.94 (Mn 0.90 2+ □ 0.10 ) ∑1.00 (□ 0.78 Li 0.17 Mg 0.05 ) ∑1.00 (Mn 3.25 2+ Fe 0.43 2+ Fe 0.09 3+ Al 0.03 ) ∑3.80 Be 4.30 (P 5.81 Si 0.08 O 24 )[(OH) 3.64 (H 2 O) 0.36 ] ∑4.00 ·6.00 H 2 O. The strongest reflection peaks of the powder diffraction pattern [ d , A ( I , %) ( hkl )] are 9.575 (53) (010), 5.998 (100) (011), 4.848 (26) (021), 3.192 (44) (210), 3.003 (14) (022), 2.803 (38) (103), 2.650 (29) (202), 2.424 (14) (231). Single-crystal unit-cell parameters are a = 6.788(2), b = 9.972(3), c = 10.014(2) A, α = 73.84(2), β = 85.34(2), γ = 87.44(2)°; V = 648.74 A 3 , Z = 1. The space group is P 1. Crystal structure was refined to R = 0.0347 with 1273 independent reflections ( F > 2σ). Footemineite is dimorphous with roscherite, and isostructural with atencioite. It is identical with the mineral from Foote mine described as “triclinic roscherite.” The name is for the Foote mine, type locality for this and several other minerals.

Zinclipscombite, a new mineral species, has been found together with apophyllite, quartz, barite, jarosite, plumbojarosite, turquoise, and calcite at the Silver Coin mine, Edna Mountains, Valmy, Humboldt County, Nevada, United States. The new mineral forms spheroidal, fibrous segregations; the thickness of the fibers, which extend along the c axis, reaches 20 μm, and the diameter of spherulites is up to 2.5 mm. The color is dark green to brown with a light green to beige streak and a vitreous luster. The mineral is translucent. The Mohs hardness is 5. Zinclipscombite is brittle; cleavage is not observed; fracture is uneven. The density is 3.65(4) g/cm3 measured by hydrostatic weighing and 3.727 g/cm3 calculated from X-ray powder data. The frequencies of absorption bands in the infrared spectrum of zinclipscombite are (cm−1; the frequencies of the strongest bands are underlined; sh, shoulder; w, weak band) 3535, 3330sh, 3260, 1625w, 1530w, 1068, 1047, 1022, 970sh, 768w, 684w, 609, 502, and 460. The Mossbauer spectrum of zinclipscombite contains only a doublet corresponding to Fe3+ with sixfold coordination and a quadrupole splitting of 0.562 mm/s; Fe2+ is absent. The mineral is optically uniaxial and positive, ω = 1.755(5), ɛ = 1.795(5). Zinclipscombite is pleochroic, from bright green to blue-green on X and light greenish brown on Z (X > Z). Chemical composition (electron microprobe, average of five point analyses, wt %): CaO 0.30, ZnO 15.90, Al2O3 4.77, Fe2O3 35.14, P2O5 33.86, As2O5 4.05, H2O (determined by the Penfield method) 4.94, total 98.96. The empirical formula calculated on the basis of (PO4,AsO4)2 is (Zn0.76Ca0.02)Σ0.78(Fe1.723+ Al0.36)Σ2.08[(PO4)1.86(AsO4)0.14]Σ2.00(OH)1. 80 · 0.17H2O. The simplified formula is ZnFe23+ (PO4)2(OH)2. Zinclipscombite is tetragonal, space group P43212 or P41212; a = 7.242(2) A, c = 13.125(5) A, V = 688.4(5) A3, Z = 4. The strongest reflections in the X-ray powder diffraction pattern (d, (I, %) ((hkl)) are 4.79(80)(111), 3.32(100)(113), 3.21(60)(210), 2.602(45)(213), 2.299(40)(214), 2.049(40)(106), 1.663(45)(226), 1.605(50)(421, 108). Zinclipscombite is an analogue of lipscombite, Fe2+Fe23+ (PO4)2(OH)2 (tetragonal), with Zn instead of Fe2+. The mineral is named for its chemical composition, the Zn-dominant analogue of lipscombite. The type material of zinclipscombite is deposited in the Mineralogical Collection of the Technische Universitat Bergakademie Freiberg, Germany.

Gjerdingenite-Mn occurs as orange-yellow to brownish prisms up to 1 mm long in miarolitic cavities of a sodic granite (’ekerite’) at Gjerdingselva, Lunner, Oppland, Oslo Region, Norway. The simplified formula is (K,Na) 2 (Mn,Fe) [(Nb,Ti) 4 (Si 4 O 12 ) 2 (O,OH) 4 ].6H 2 O. It is the Mn-dominant analogue of gjerdingenite-Fe, the Ti analogue of kuzmenkoite-Mn and a dimorph of organovaite-Mn. The mineral is monoclinic, C 2/ m , with a = 14.563(3), b = 13.961(3), c = 7.851(2) A, β = 117.62(3)°, V = 1414.3(6) A 3 , Z = 2. The crystal structure was refined to R ( F ) = 0.079 on the basis of 1207 observed reflections and is compared to the structure of gjerdingenite-Fe. The strongest five reflections of the X-ray powder-diffraction pattern [d obs in A ( I ) ( hkl )] are: 6.96 (100) (020, 001), 4.94 (80) (021), 3.22 (90) (42-1, 400, 40-2), 3.10 (80) (041, 022) and 2.510 (40) (44-1, 401, 40-3, 042). The mineral is optically biaxial (+) with α = 1.670(2), β = 1.685(2), γ = 1.775(5); 2V meas = 52(8)°, 2V calc = 46(5)°. The axial dispersion is weak, r a , Y = b . Mohs hardness is about 5; D calc = 2.93 g/cm 3 . The pseudo-orthorhombic crystals are twinned on {001}, elongate along [010] and show the forms {001}, {100}, {201} and {021}. Some general aspects on the formation of labuntsovite-group minerals are discussed.

Larisaite, a new uranyl selenite with the idealized formula Na(H3O)(UO2)3(SeO3)2O2 · 4H2O, has been found in a sedimentary rock from Repete mine near Blanding, San Juan Co., Utah, U.S.A., in association with quartz, haynesite, andersonite, wolsendorfite, uranophane, gypsum, calcite and montmorillonite. The mineral is named in memory of Russian mineralogist and crystallographer Larisa Nikolaevna Belova (1923–1998) who made a significant contribution to the knowledge on the uranium minerals. Larisaite forms coarse lamellar crystals up to 1 mm and radial aggregates up to 2 mm. It is transparent or translucent, yellow, lustre vitreous, streak yellow. Fluorescence under the UV light is green (wavelengths of excitation 250 nm). Larisaite is sectile, with Mohs' hardness 1, perfect cleavage on (010) and uneven fracture across the cleavage direction. Calculated density is 4.50 g/cm3 from the crystal structure refinement and 4.46 g/cm3 from the empirical formula. Optically biaxial (−), α 1.597(2), β 1.770(5), γ 1.775(5); −2V = 20°. Dispersion is strong, r α (light greenish-yellow). IR spectrum is given. Average values for 3 point microprobe analyses (wt.%, ranges are given in brackets) are: Na2O 2.04 (1.82–2.32), K2O 0.69 (0.62–0.76), CaO 0.23 (0.17–0.30), UO3 72.19 (71.77–72.64), SeO2 18.12 (17.83–18.48); H2O content determined by Penfield method is 7.64; total 100.91 wt.%; contents of Mg, Sr, Ba, Pb, Zn, Mn, Ni, Co, Cu, Fe, Al, Si, S, As, Cl, F are lower than detection limits i. e. 2)3.09(SeO3)2O24.1H20.1-(Kp/Kc) = 0.013 (“superior”). The crystal structure has been determined (R=0.067). Larisaite is monoclinic, space group P 11 m ; a = 6.9806(9), b = 7.646(1), c = 17.249(2) A, γ = 90.039(4)°, V = 920.64 A3, Z = 2. The strongest lines in the powder diffraction pattern [ d , A ( I , %) ( hkl )] are: 8.63 (43) (002), 7.67 (100) (010), 3.85 (40) (−113, 020, 113), 3.107(77) (211), 2.874 (53) (006, −115). By the U: Se ratio, the values of unit cell parameters and the structure type, larisaite is related to haynesite, guilleminite and piretite. In common with guilleminite, uranium polyhedra and SeO3 triangles form the sheets, however the distribution of interlayer cations and H2O molecules is different. Holotype specimen is deposited in the Geoscientific Collections of Freiberg University of Mining and Technology, Faculty of Geosciences, Geotechnics and Mining, Freiberg, Germany (the inventory number 80251).

Ruifrancoite, Ca 2 (□,Mn 2+ ) 2 (Fe 3+ ,Mg,Mn 2+ ,Fe 2+ ,Al) 4 Be 4 (PO 4 ) 6 (OH) 4 (OH,H 2 O) 2 ·4H 2 O, monoclinic, is a newly recognized member of the roscherite group. It occurs as a late vug-filling mineral in albite and muscovite, closely associated with cyrilovite and meurigite in a granite pegmatite at the Sapucaia (Proberil) mine, Sapucaia do Norte, Galileia County, Minas Gerais, Brazil. Ruifrancoite occurs as needles or laths 1 to 2 μm thick and up to 100 μm long in fan-shaped botryoidal arrangements. The color is reddish brown, the streak is orange-brown, and the luster is vitreous. Ruifrancoite is transparent and non-fluorescent. The measured density is 2.88(1) g/cm 3 (by the hydrostatic weighing method), and the calculated density is 2.859 g/cm 3. The mineral is biaxial (+), α 1.665(3), β1.665(3), γ1.682(3) (white light), 2 V (obs.) 0–10°, 2 V (calc.) 0°. The orientation is X = b , Y ^ c ≈ 16°; dispersion r > ν , very strong. Pleochroism is γ(brownish red) > α = β(light brownish red). Infrared and Mossbauer spectroscopic data are given. The chemical composition is (wt.%, EDS mode, electron microprobe, Fe 2+ :Fe 3+ ratio by Mossbauer data): CaO 9.81, MgO 3.23, MnO 8.10, FeO 3.93, Fe 2 O 3 12.51, Al 2 O 3 0.86, BeO (by ICP–AES) 8.41, P 2 O 5 39.46, H 2 O (by Penfield method) 12.56, total 98.87. The empirical formula, based on six (PO 4 ) groups, with calculated BeO of 9.23%, is Ca 1.89 (□ 1.45 Mn 2+ 0.55 ) ∑2.00 (Fe 3+ 1.69 Mg 0.86 Mn 2+ 0.68 Fe 2+ 0.59 Al 0.18 ) ∑4.00 Be 4.00 (PO 4 ) 6 [(OH) 4.75 (H 2 O) 1.25 ]·3.90H 2 O. The ideal end-member formula of ruifrancoite is Ca 2 □ 2 Fe 3+ 4 Be 4 (PO 4 ) 6 (OH) 6 ·4H 2 O. The strongest reflections of the powder-diffraction pattern [ d in A( I )( hkl )] are: 9.485(44)(110), 5.943(100)(020), 4.821(65)(310), 3.176(44)(330), 2.784(41)(240), and 2.643(42)(600). The unit-cell parameters refined from powder data are a 15.911(7), b 11.894(7), c 6.625(7) A, β94.5(1)°, V 1250(1) A 3 , Z = 2. The space group is C 2/ c . The mineral is named in honor of Professor Rui Ribeiro Franco (b. 1916), in recognition of his outstanding contributions to Brazilian mineralogy and geology. Former descriptions of “roscherite” at Sapucaia mine, and “Fe 3+ -dominant species” at Pomarolli farm, Linopolis, Divino das Laranjeiras, Minas Gerais, Brazil, should be considered to refer to ruifrancoite.