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Yusupovite, ideally Na2Zr(Si6O15)(H2O)3, is a new silicate mineral from the Darai-Pioz alkaline massif in the upper reaches of the Darai-Pioz river, area of the joint Turkestansky, Zeravshansky, and Alaisky ridges, Tajikistan. Yusupovite was found in a pegmatite composed mainly of reedmergnerite, aegirine, microcline, and polylithionite. It occurs as prismatic grains about 2 mm in size embedded in reedmergnerite; associated minerals are quartz, pectolite, zeravshanite, mendeleevite-(Ce), fluorite, leucosphenite, a pyrochlore-group mineral, neptunite, telyushenkoite, moskvinite-(Y), and shibkovite. Yusupovite is colorless, transparent with a white streak, has a vitreous luster, and does not fluoresce under ultraviolet light. Cleavage is perfect on {110}, parting was not observed. Mohs hardness is 5. Yusupovite is brittle with a splintery fracture. The measured and calculated densities are 2.69(2) and 2.713 g/cm³, respectively. Yusupovite is optically biaxial (+) with refractive indices (λ = 589 nm) α = 1.563(2), β = 1.565(2), γ = 1.577(2); 2Vmeas = 42(3)°, 2Vcalc = 45°, strong dispersion: r > v. Yusupovite is monoclinic, C2/m, a = 14.5975(4), b = 14.1100(4), c = 14.4394(4) Å, β = 90.0399(4)°, V = 2974.1(3) ų. The six strongest reflections in the X-ray powder diffraction data [d (Å), I, (hkl)] are 7.05, 100, (020); 3.24, 96, (420); 3.10, 69, (241, 241); 5.13, 53, (202, 202); 6.51, 42, (201, 201); 3.17, 34, (042). The chemical composition (electron microprobe) is: Nb2O5 0.39, SiO2 58.84, ZrO2 16.55, HfO2 0.30, FeO 0.01, Y2O3 3.05, Cs2O 2.58, K2O 0.95, Na2O 8.91, H2Ocalc 7.40, total 98.98 wt%, with H2O calculated from structure refinement. The empirical formula (based on 17.5 O apfu) is (Na1.76K0.12Cs0.11)Σ1.99 (Zr0.82Y0.17Nb0.02Hf0.01)S1.02(Si6.01O14.98)(H2O)2.52, Z = 8. The crystal structure of yusupovite was refined to R1 = 3.46% based on 4428 observed reflections. In the crystal structure, there are six Si sites occupied by Si, two M sites occupied mainly by Zr with minor Y and Hf. Si tetrahedra form an epididymite Si6O15 ribbon along [010]. Epididymite ribbons and Zr-dominant M octahedra share common vertices to form a heteropolyhedral Si-Zr-O framework. There are six interstitial sites partly occupied by alkali cations Na, K, and Cs. The three [7]-coordinated Na sites are occupied by Na at 95, 84, and 78%. The three A sites are occupied by K and Cs at 12, 18, and 16%. There are 10 W sites occupied by H2O groups at 18-84%. Due to (K,Cs), Na and H2O disorder, the symmetry of yusupovite decreases from orthorhombic, space group Pbcm (elpidite), to monoclinic, space group C2/m, and the b unit-cell parameter of yusupovite is doubled compared to the corresponding cell parameter in elpidite, byus = 2aelp. Yusupovite, ideally Na2Zr(Si6O15)(H2O)3, is a dimorph of elpidite, Na2Zr(Si6O15)(H2O)3. [ABSTRACT FROM AUTHOR]

Laptevite-(Ce), ideally NaFe2+(REE7Ca5Y3) · (SiO4)4(Si3B2PO18)(BO3)F11, is a new member of the vicanite group discovered in the moraine of the Darai-Pioz glacier, Alai Mountain Range, Tien-Shan, Tajikistan. The crystal structure of laptevite-(Ce), trigonal, a = 10.804(2) Å , c = 27.726(6) Å , V = 2802.6(2) Å 3, sp. gr. R3m, Z = 3, Dcalc. = 4.660 · 103 kg/m3, has been refined to R1 = 0.0387 for 924 unique (Fo > 4σF) reflections, collected on a Bruker single-crystal P4 diffractometer with a 4K CCD detector and Mo-Ka X-radiation. The simplified formula is NaFe2+(REE,Ca,Y)15(SiO4)4 [(Si,B,P)6O18](BO3)F11. In the crystal structure of laptevite-( Ce), there are four tetrahedrally coordinated T sites. The T(1) site is occupied by Si and minor B, 〈T(1)-O〉 = 1.594 Å ; the T(2, 3) sites are occupied by Si, 〈T(2,3)-O〉 = 1.64 Å ; the T(4) site is occupied by B, P and minor Si, with 〈T(4)-O〉 = 1.51 Å . The [3]-coordinated T(5) site has composition B0.84⃞0.16, with 〈T(5)-O〉 = 1.42 Å . Cations at the T(1 + 4), T(2, 3) and T(5) sites form the complex anions (Si3B2PO18), (SiO4)4 and (BO3), respectively. The [7-10-coordinated M(1-5) sites are occupied by REE, Ca, Y and minor Sr, with 〈M(1-5)-O〉 = 2.37-2.62 Å . The octahedrally coordinated M(6) site is occupied by Fe2+ > Mn > Ti, with 〈M(6)-O〉 =2.13 Å . The [10]-coordinated M(7) site has composition Na0.75REE0.25, with 〈M(7)-O〉 = 2.64 Å . The T and M polyhedra form a framework. Laptevite-(Ce) is isostructural with other vicanite-group minerals: vicanite- (Ce), okanoganite-(Y), hundholmenite-(Y) and proshchenkoite-(Y). Vicanite-group structures differ in the dominant cation species at the T(1, 3-6) and M(3-7) sites. [ABSTRACT FROM AUTHOR]

The new mineral axelite, ideally Na14Cu7(AsO4)8F2Cl2, was found in the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with sylvite, halite, arsmirandite, bradaczekite, johillerite, tilasite, ericlaxmanite, lammerite, hematite, tenorite, cassiterite, pseudobrookite, aphthitalite-group sulfates, anhydrite, fluoborite, sanidine and fluorophlogopite. Axelite occurs as tabular, quadratic, rectangular or stronger distorted crystals up to 0.02 × 0.1 × 0.1 mm, sometimes combined in interrupted crusts up to 0.4 mm across overgrowing sylvite. It is transparent, sky-blue, with vitreous lustre. Cleavage was not observed. D calc is 3.662 g cm–3. Axelite is optically uniaxial (–), ɛ = 1.650(4) and ω = 1.678(4). Chemical composition (wt.%, electron microprobe data) is: Na2O 22.54, K2O 0.08, CaO 0.04, MgO 0.05, CuO 26.69, P2O5 1.75, V2O5 0.15, As2O5 44.14, SO3 0.04, F 1.57, Cl 3.60, –O=(F,Cl) –1.47, total 99.18. The empirical formula based on O+F+Cl=36 apfu is Na14.37K0.03Ca0.01Mg0.02Cu6.63P0.49V0.03As7.59S0.01O32.36F1.63Cl2.01. Axelite is tetragonal, P 4 bm , a = 14.5957(2), c = 8.34370(18) Å, V = 1777.51(6) Å3 and Z = 2. The strongest reflections of the powder X-ray diffraction (XRD) pattern [ d ,Å(I)(hkl)] are: 8.32(44)(001), 5.156(47)(220), 4.168(21)(002), 3.246(34)(222), 3.180(61)(331), 2.747(100)(402), 2.709(36)(511) and 2.580(29)(440). The crystal structure, solved from single-crystal XRD data (R = 4.50%), is unique. It is based on the heteropolyhedral chains built by clusters formed by CuO4Cl square pyramids connected with AsO4 tetrahedra. Adjacent chains are connected via common vertices of AsO4 tetrahedra with CuO4Cl pyramids to form a heteropolyhedral pseudo-framework. Axelite is remotely related, in both structural and chemical aspects, to lavendulan-like minerals and synthetic compounds. The mineral is named in honour of the outstanding Finnish–Russian crystallographer, mineralogist and material scientist Axel Gadolin (1828–1892). [ABSTRACT FROM AUTHOR]

Three new borate minerals rhabdoborite-(V), rhabdoborite-(Mo) and rhabdoborite-(W), forming the rhabdoborite group, are found in the Arsenatnaya fumarole, Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. They are closely associated with each other and anhydrite, diopside, hematite, schäferite, berzeliite, svabite, calciojohillerite, ludwigite, forsterite, magnesioferrite, baryte, fluorapatite, udinaite, arsenudinaite, and powellite. Rhabdoborites form long-prismatic to acicular crystals up to 0.04 × 0.04 × 7 mm3 typically combined in aggregates up to 1 cm. They are transparent, light yellow, with vitreous lustre. The empirical formulae of holotypes, calculated based on 26 O + F apfu, are: rhabdoborite-(V): (Mg11.85Fe3+0.11Mn0.06Ca0.02)Σ12.04(V5+0.70Mo6+0.36W6+0.21Te6+0.01)Σ1.28[(P0.35As5+0.16)Σ0.51B5.50]Σ6.01O24.35F1.65; rhabdoborite-(Mo): (Mg11.78Mn0.07Fe3+0.06Ca0.06)Σ11.97(Mo6+0.65V5+0.49W6+0.19)Σ1.33[(P0.31As5+0.14)Σ0.45B5.54]Σ5.99O24.33F1.67; rhabdoborite-(W): (Mg11.74Fe3+0.09Ca0.03Mn0.02)Σ11.88(W6+0.75V5+0.44Mo6+0.13)Σ1.32[(P0.25As5+0.13)Σ0.38B5.65]Σ6.03O24.42F1.58. The simplified formulae are: rhabdoborite-(V): Mg 12 (V 5 + , M 6 +) 1 1 3 O 6 {(BO3)6–x(PO4)xF2–x} (M6+ = Mo, W and x < 1); rhabdoborite-(Mo): Mg 12 Mo 1 1 3 6 + O 6 (BO3)6F2; rhabdoborite-(W): Mg 12 W 1 1 3 6 + O 6 (BO3)6F2. Rhabdoborites are hexagonal, P63, and Z = 1. The unit-cell parameters of rhabdoborite-(V)/rhabdoborite-(Mo)/rhabdoborite-(W) are: a 10.6314(4)/10.6304(3)/10.6366(5), c 4.5661(2)/4.56374(16)/4.5701(3) Å, and V 446.95(3)/446.63(3)/447.78(4) Å3. The crystal structures were solved from single-crystal XRD data, R1 = 0.0413, 0.0289 and 0.0418 for rhabdoborite-(V), rhabdoborite-(Mo) and rhabdoborite-(W), respectively. These isostructural minerals represent a novel structure type. The structure is based on a three-dimensional network (pseudo-framework) built by the (0001) layers formed by clusters Mg6O21F composed by Mg-centred octahedra and linked via BO3 triangles. The distorted octahedra MO6 (M = V5+, Mo6+, W6+) are located in gaps in the layers. The pair of anions, (BO3)3− triangle and adjacent F−, is partially substituted by the (P,As5+)O43− tetrahedral anion. Rhabdoborites form a continuous solid-solution system in which contents of V, Mo and W are the main varying values. The rootname rhabdoborite reflects morphological (rhabdos is rod, in Greek) and chemical (borate) features of the minerals; the suffix-(V), -(Mo) or -(W) indicates predominant, species-defining M component. [ABSTRACT FROM AUTHOR]

The new mineral zilbermintsite-(La), ideally (CaLa5)(Fe3+Al3Fe2+)[Si2O7][SiO4]5O(OH)3, was found in a single polymineralic nodule from the Mochalin Log REE deposit, Chelyabinsk Oblast, South Urals, Russia. Zilbermintsite-(La) forms anhedral grains up to 0.65 × 0.20 mm at the contact of ferriperbøeite-(La), törnebohmite-(La) and ferriallanite-(Ce). Other associated minerals include bastnäsite-(La), biraite-(La), ferriallanite-(La), ferriperbøeite-(Ce), fluorbritholite-(Ce), monazite-(La), perbøeite-(La), percleveite-(Ce), percleveite-(La), perrierite-(Ce), perrierite-(La), thorianite, thorite and quartz. The new mineral is light brown, translucent in thin fragments with a vitreous lustre. It is brittle, with good {100} cleavage. Mohs hardness is ca. 6. D calc = 4.684 g cm–3. Optically, zilbermintsite-(La) is biaxial (+), α = 1.805(7), β = 1.812(7) and γ = 1.867(8) (589 nm); 2Vmeas = 40(15)° and 2Vcalc = 40°. The empirical formula based on O28(OH,F)3 apfu is (Ca0.94La2.56Ce2.18Nd0.20Pr0.10Th0.02)Σ6.00(Al2.96Fe3+0.90Fe2+0.64Mg0.34Mn0.13Ti0.03)Σ5.00Si7.00O28[(OH)2.42F0.58]. Zilbermintsite-(La) is monoclinic, P 21/ m ; the unit-cell parameters are: a = 8.9605(5), b = 5.7295(2), c = 25.1033(13) Å, β = 116.616(7), V = 1152.21(12) Å3 and Z = 2. The crystal structure of zilbermintsite-(La) is solved from the single-crystal X-ray diffraction data [ R = 0.0757 for 2857 unique reflections with I > 2σ(I)]. The new mineral is isotypic to radekškodaite-(La) and radekškodaite-(Ce) and together with them forms the newly defined radekškodaite group. All members of this group possess the ET2 type structure where one epidote-type module (E) regularly alternates with two törnebohmite-type modules (T). The new mineral honours Professor Veniamin A. Zilbermints (1887–1939) who was a pioneer of the study of the Mochalin Log deposit. The Levinson suffix-modifier -(La) indicates the predominance of La among rare-earth elements in the mineral. [ABSTRACT FROM AUTHOR]

The new mineral patynite was discovered at the massif of Patyn Mt. (Patynskiy massif), Tashtagolskiy District, Kemerovo (Kemerovskaya) Oblast', Southern Siberia, Russia. Patynite forms lamellae up to 1 × 0.5 cm and is closely intergrown with charoite, tokkoite, diopside, and graphite. Other associated minerals include monticellite, wollastonite, pectolite, calcite, and orthoclase. Patynite is colorless in individual lamellae to white and white-brownish in aggregates. It has vitreous to silky luster, white streaks, brittle tenacity, and stepped fractures. Its density measured by flotation in Clerici solution is 2.70(2) g/cm3; density calculated from the empirical formula is 2.793 g/cm3. The Mohs' hardness is 6. Optically, patynite is biaxial (−) with α = 1.568(2), β = 1.580(2), and γ = 1.582(2) (589 nm). The 2V (measured) = 40(10)° and 2V (calculated) = 44.1°. The Raman and IR spectra shows the absence in the mineral of H2O, OH−, and CO32− groups and B–O bonds. The chemical composition is (electron microprobe, wt.%): Na2O 3.68, K2O 5.62, CaO 26.82, SiO2 64.27, total 100.39. The empirical formula based on 23 O apfu is Na1.00K1.00Ca4.02Si8.99O23. Patynite is triclinic, space group P 1. The unit-cell parameters are: a = 7.27430(10), b = 10.5516(2), c = 13.9851(3) Å, α = 104.203(2)°, β = 104.302(2)°, γ = 92.0280(10)°, V = 1003.07(3) Å3, Z = 2. The crystal structure was solved by direct methods and refined to R1 = 0.032. Patynite is an inosilicate with a new type of sextuple branched tubular chain [(Si9O23)10−]∞ with an internal channel and [(Si18O46)20−] as the repeat unit. The strongest lines of the powder X-ray diffraction pattern [dobs, Å (I, %) (hkl)] are: 3.454 (100) (2-1-1), 3.262 (66) (2-1-2), 3.103 (64) (02-4), 2.801 (21), 1.820 (28) (40-2). Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia with the registration number 5369/1. [ABSTRACT FROM AUTHOR]

The new columbite-supergroup mineral dmitryvarlamovite, ideally Ti2(Fe3+Nb)O8, was discovered in weathered alkaline metasomatic assemblages formed after late Riphaean sedimentary carbonate rocks of the Verkhne-Shchugorskoe deposit, Middle Timan Mts., Russia. The associated minerals are columbite-(Fe), pyrochlore-group minerals, monazite-(Ce), xenotime-(Y), baryte, pyrite, drugmanite and plumbogummite. Dmitryvarlamovite occurs as isolated anhedral equant grains up to 0.5 mm across. The colour of dmitryvarlamovite is black, the streak is black and the lustre is submetallic. The new mineral is brittle, with the mean VHN hardness of 753 kg mm–2 corresponding to the Mohs' hardness of 6. No cleavage is observed. The fracture is conchoidal. The calculated density is 4.891 g⋅cm–3. In reflected light, dmitryvarlamovite is light grey; no pleochroism is observed. The reflectance values (R min, % / R max, % / λ, nm) are: 19.8/20.3/470, 18.3/18.9/546, 17.8/18.5/589 and 17.3/17.8/650. The chemical composition is (electron microprobe data, with iron divided into Fe2O3 and FeO based on the charge balance, wt.%): MnO 0.11, FeO 1.51, V2O3 0.89, Cr2O3 0.28, Fe2O3 19.26, TiO2 37.72, Nb2O5 40.08, total 99.85. The IR and Raman spectra indicate the absence of H-, C- and N-bearing groups. The empirical formula is (Fe2+0.08V3+0.05Cr3+0.01Fe3+0.92Ti1.79Nb1.15)Σ4.00O8. The crystal structure was determined using single-crystal X-ray diffraction data and refined to R = 0.048. Dmitryvarlamovite is orthorhombic, space group P 21212, a = 4.9825(6), b = 4.6268(4), c = 5.5952(6) Å and V = 5.5952(6) Å3 (Z = 1). The structure is related to those of wolframite-group minerals but differs in the scheme of cation ordering. The crystal-chemical formula derived based on the structural data is (Ti0.57Nb0.21Fe3+0.15Fe2+0.04V0.02Cr0.01)2(Nb0.36Ti0.33Fe3+0.31)2O8. The strongest lines of the powder X-ray diffraction pattern [ d , Å (I , %) (hkl)] are: 3.58 (40) (011), 2.911 (100) (111), 2.809 (40) (002), 2.497 (38) (020), 2.447 (29) (103), 1.7363 (32) (103) and 1.7047 (29) (220). Dmitryvarlamovite is named after Dmitry Anatol'evich Varlamov (b. 1965). [ABSTRACT FROM AUTHOR]

The new mineral zubkovaite, Ca3Cu3(AsO4)4, was found in the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with anhydrite, svabite, hematite, johillerite, tilasite, fluorophlogopite, sanidine and aphthitalite. Zubkovaite occurs as coarse prismatic crystals up to 0.01 mm × 0.01 mm × 0.2 mm combined in radiating aggregates or crusts. The mineral is transparent, bright sky-blue, turquoise-coloured or light bluish-green, with vitreous lustre. It is brittle, with imperfect cleavage. The Mohs' hardness is ca 3. D calc is 4.161 g cm–3. Zubkovaite is optically biaxial (–), α = 1.747(5), β = 1.774(5), γ = 1.792(5) and 2Vmeas = 75(10)°. Chemical composition (wt.%, electron microprobe) is: CaO 19.22, CuO 27.37, As2O5 52.54, SO3 0.67, total 99.80. The empirical formula based on 16 O apfu is Ca2.96Cu2.97(As3.945S0.07)Σ4.015O16. Zubkovaite is monoclinic, C 2, a = 16.836(3), b = 5.0405(8), c = 9.1173(17) Å, β = 117.388(13)°, V = 687.0(2) Å3 and Z = 2. The strongest reflections of the powder XRD pattern [ d ,Å (I) (hkl)] are: 7.44 (100) ($\bar 2$ 01), 3.727 (79) (400, $\bar 2$ 02, $\bar 3$ 11), 3.334 (92) ($\bar 1$ 12), 2.914 (73) (311), 2.765 (50) ($\bar 6$ 01, $\bar 6$ 02), 2.591 (96) ($\bar 3$ 13) and 2.521 (53) (020). The crystal structure is unique for minerals. It was solved from single-crystal X-ray diffraction data to R = 7.19%. The structure contains trimers of Cu2+-centred polyhedra (consisting of one distorted square CuO4 in the core and two distorted square pyramids CuO5) and two crystallographically independent As5+O4 tetrahedra playing different roles: As(2)O4 tetrahedra link neighbouring trimers into ribbons whereas As(1)O4 tetrahedra link adjacent ribbons into heteropolyhedral layers; Ca cations are located in the interlayer space. The mineral is named in honour of the Russian crystallographer and crystal chemist Natalia Vital'evna Zubkova (born 1976). [ABSTRACT FROM AUTHOR]

A new mineral cuprodobrovolskyite, ideally Na4Cu(SO4)3, was found in sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with petrovite, saranchinaite, euchlorine, krasheninnikovite, langbeinite, calciolangbeinite, anhydrite, sanidine, tenorite and hematite. Cuprodobrovolskyite occurs as coarse hexagonal tabular or equant, typically skeletal crystals up to 1 mm and their clusters or crusts up to 1.5 cm × 2.5 cm in area. The mineral is transparent, light blue or greenish-bluish to almost colourless with vitreous lustre. Cuprodobrovolskyite is optically uniaxial (+) with ω = 1.509(3) and ε = 1.528(3). The empirical formula calculated on the basis of 12 O apfu is (Na3.64K0.09Pb0.03)Σ3.76(Cu0.51Ca0.22Mg0.16Zn0.07Al0.01Mn0.01)Σ0.98S3.04O12. The unit-cell parameters of cuprodobrovolskyite calculated from the powder X-ray diffraction data are: a = 15.702(2), c = 22.017(5) Å, V = 4701.0(2) Å3, space group R 3 and Z = 18. The crystal structure was studied using the Rietveld method, R p = 0.0246, R wp = 0.0325, R 1 = 0.0521 and wR 2 = 0.0770. Cuprodobrovolskyite is an isostructural analogue of dobrovolskyite Na4Ca(SO4)3 with Cu prevailing over Ca. One of the main features of cuprodobrovolskyite is Cu2+ in 7-fold coordination. On the basis of relationships with saranchinaite Na2Cu(SO4)2 and petrovite Na12Cu2(SO4)8 in the Arsenatnaya fumarole and the results of heating experiments, cuprodobrovolskyite is considered as the highest-temperature phase among anhydrous Na–Cu sulfate minerals. [ABSTRACT FROM AUTHOR]

Two new isostructural minerals edtollite K2NaCu5Fe3+O2(AsO4)4 and alumoedtollite K2NaCu5AlO2(AsO4)4 have been found in the Arsenatnaya fumarole, Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. They are associated with sylvite, tenorite, dmisokolovite, shchurovskyite, johillerite, bradaczekite, and orthoclase. Edtollite forms prismatic crystals up to 0.02 mm × 0.1 mm; alumoedtollite forms long-prismatic crystals up to 0.01 mm × 0.1 mm. Both minerals have a semi-metallic lustre. Edtollite is brown–black to black and alumoedtollite is bronze coloured. D calc. = 4.26 (edtollite) and 4.28 (alumoedtollite) g cm–3. In reflected light, both minerals are grey, with distinct anisotropy. Reflectance values [edtollite/alumoedtollite: R 1– R 2, % (λ, nm)] are: 8.3–8.2/8.7–7.7 (470); 7.7–7.4/8.3–7.4 (546); 7.1–6.9/8.3–7.4 (589); and 6.3–6.3/7.6–7.2 (650). Chemical data are: (edtollite/alumoedtollite, wt.%, electron-microprobe): Na2O 3.13/2.58, K2O 8.12/9.09, Rb2O 0.00/0.11, CaO 0.00/0.52, CuO 36.55/38.35, ZnO 0.46/0.00, Al2O3 0.00/3.48, Fe2O3 7.34/1.79, TiO2 0.27/0.00, As2O5 43.57/43.66, total 99.44/99.58. The empirical formulae, based on 18 O apfu, for edtollite is: K1.83Na1.07Cu4.88Zn0.06Fe3+0.98Ti0.04As4.03O18; and for alumoedtollite is: K2.02Rb0.01Na0.87Ca0.10Cu5.06Al0.72Fe3+0.24As3.99O18. Both minerals are triclinic, P $\bar{1}$ ; unit-cell parameters (edtollite/alumoedtollite) are: a = 5.1168(6)/5.0904(11), b = 9.1241(12)/9.0778(14), c = 9.6979(14)/9.6658(2) Å, α = 110.117(13)/110.334(17), β = 102.454(12)/102.461(19), γ = 92.852(11)/92.788(15)°, V = 411.32(9)/404.88(14) Å3 and Z = 1/1. The strongest reflections in the powder X-ray diffraction pattern [ d ,Å(I)(hkl)] are for edtollite: 8.79(92)(001), 7.63(41)(0 $\bar{1}$ 1), 5.22(44)(011), 3.427(100)(012), 3.148(64)(0 $\bar{1}$ 3), 2.851(65)($\bar{1}$ 03) and 2.551(40)($\bar{2}$ 01); and for alumoedtollite: 8.78(81)(001), 7.62(67)(0 $\bar{1}$ 1), 3.418(100)(012), 3.147(52)(0 $\bar{1}$ 3), 2.558(58)($\bar{1}$ 22), 2.544(65)($\bar{2}$ 01) and 2.528(52)($\bar{1}\bar{3}$ 2). The crystal structures [single-crystal X-ray diffraction, R = 0.0773 (edtollite) and 0.0826 (alumoedtollite); 1504 and 1046 unique reflections, respectively] represent a novel structure type. It is based upon a heteropolyhedral pseudo-framework with the column formed by Cu2+-centred octahedra and square pyramids, octahedra M O6 (M = Fe3+, Al3+ or Cu2+) and AsO4 tetrahedra as the main building unit. K+ and Na+ are located in wide and narrow channels, respectively. Edtollite is named after the Russian geologist and Arctic explorer Eduard Vasilievich Toll (1858–1902), alumoedtollite is its analogue with Al prevailing among trivalent cations. [ABSTRACT FROM AUTHOR]

The new durangite-group mineral arsenatrotitanite, ideally NaTiO(AsO4), was found in the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with orthoclase, tenorite, hematite, johillerite, bradaczekite, badalovite, calciojohillerite, arsmirandite, tilasite, svabite, cassiterite, pseudobrookite, rutile, sylvite, halite, aphthitalite, langbeinite and anhydrite. Arsenatrotitanite occurs as prismatic, tabular, lamellar or acicular crystals up to 0.3 mm × 0.8 mm × 2 mm. They are separated or combined in open-work aggregates up to 2 mm across or interrupted crusts up to 2 mm × 5 mm in area and up to 0.3 mm thick. Arsenatrotitanite is transparent, brownish red to pale pinkish-reddish or almost colourless, with vitreous lustre. It is brittle and the Mohs' hardness is ~5½. Cleavage is perfect on {110} and the fracture is stepped. D calc is 3.950 g cm–3. Arsenatrotitanite is optically biaxial (+), α = 1.825(5), β = 1.847(6), γ = 1.896(6) (589 nm) and 2Vmeas. = 70(5)°. Chemical composition (wt.%, electron-microprobe) is: Na2O 12.26, CaO 3.10, Al2O3 4.39, Fe2O3 9.57, TiO2 17.11, SnO2 1.03, As2O5 50.17, F 3.29, O = F –2.39, total 99.53. The empirical formula based on 5 (O + F) apfu is (Na0.91Ca0.13)Σ1.04(Ti0.49Fe3+0.27Al0.20Sn0.02)Σ0.98(As1.00O4.00)(O0.60F0.40). Arsenatrotitanite is monoclinic, C 2/ c , a = 6.6979(3), b = 8.7630(3), c = 7.1976(3) Å, β = 114.805(5)°, V = 383.48(3) Å3 and Z = 4. The strongest reflections of the powder X-ray diffraction (XRD) pattern [ d ,Å(I)(hkl)] are: 4.845(89)($\bar{1} {11}}$), 3.631(36)(021), 3.431(48)(111), 3.300(100)($\bar{1} {12}}$), 3.036(100)(200), 2.627(91)(130) and 2.615(57)(022). The crystal structure was solved from single-crystal XRD data with R = 1.76%. Arsenatrotitanite belongs to the titanite/durangite structure type. It is named as an arsenat e of sodium (natr ium in Latin) and titani um isostructural with titanite. [ABSTRACT FROM AUTHOR]

An investigation of sample 41647 from the Platinum Placer of Ugol'nyi Ruchei, Norilsk Cu–Ni deposit, Russia, stored in the systematic collection of the Fersman Mineralogical Museum, revealed that it contained a mineral that can be identified as the original stannopalladinite described in 1947. As the literature information on the latter is controversial, the mineral was re-investigated using modern analytical techniques. Stannopalladinite occurs as spherical and ovoid-shaped grains up to 0.08 mm, closely intergrown with tetraferroplatinum as part of flattened, prismatic crystals up to 6 mm long. The micro-indentation hardness of stannopalladinite (VHN, 30 g load) is 244 kg/mm2 (range 233–266, n = 4), corresponding to a Mohs hardness of 4. The calculated density is 9.781 g/cm3. In reflected light, stannopalladinite is pale pink. The bireflectance is noticeable only in oil immersion. In crossed nicols the mineral exhibits strong anisotropy with colour effects changing from reddish purple to greyish blue and polysynthetic twinning of grains. The reflectance curves show distinct anomalous dispersion. The chemical composition (wt.%, electron microprobe data, mean of 11 analyses) is: Cu 8.48, Pd 61.21, Pt 0.89, Sn 25.87, Pb 3.70, total 100.15. The empirical formula calculated on the basis of 4 atoms per formula unit is (Pd2.42Cu0.56Pt0.02)Σ3.00(Sn0.92Pb0.08)Σ1.00. The ideal chemical formula of stannopalladinite is therefore proposed as (Pd,Cu)3Sn instead of Pd3Sn2 used in the official IMA List of Minerals. The strongest powder X-ray diffraction lines are [ d obs, Å (I , %) (hkl) ]: 2.292 (42) (231), 2.166 (100) (331), 2.034 (10) (710), 1.916 (15) (141) and 1.851 (15) (630). The powder X-ray data are indexed in the orthorhombic unit cell with a = 14.634(2), b = 8.5253(6), c = 4.5946(3) Å and V = 573.24(7) Å3 (Z = 8). Stannopalladinite can be reliably identified among all other minerals belonging to the binary Pd–Sn and ternary Pd–Cu–Sn systems by a combination of chemical, optical and X-ray data. [ABSTRACT FROM AUTHOR]

Napoliite, ideally Pb2OFCl, is a new fluoroxychloride mineral found in a specimen from a fumarole formed subsequent to the 1944 eruption of Vesuvius volcano, Naples Province, Italy. It occurs as well-shaped lamellar crystals up to 0.25 × 0.25 × 0.01 mm typically forming clusters up to 0.4 × 0.4 mm on the surface of volcanic scoria in association with anglesite, artroeite, atacamite, calcioaravaipaite, cerussite, challacolloite, cotunnite, hephaistosite, manuelarossiite, matlockite and susannite. Napoliite is colourless with white streak and adamantine lustre. It is brittle and has a laminated fracture. Cleavage is perfect on {001}. D calc = 7.797 g cm–3. The calculated mean refractive index is 2.10. Chemical composition (wt.%, electron microprobe) is: PbO 91.71, F 3.89, Cl 7.34, –O=(F+Cl) –3.30, total 99.64. The empirical formula calculated on the basis of 3 anions is Pb1.999O0.997F0.996Cl1.007. Raman spectroscopy confirms the absence of OH– groups and H2O molecules in the mineral. Napoliite is tetragonal, space group P 42/ mcm , a = 5.7418(11), c = 12.524(4) Å, V = 412.9(2) Å3 and Z = 4. The strongest lines of the powder X-ray diffraction pattern [ d , Å (I , %) (hkl)] are: 3.860 (85) (111); 3.139 (20) (004); 2.914 (100) (113); 2.866 (63) (200); 2.118 (19) (204); 2.027 (19) (220); 1.665 (20) (313); and 1.642 (23) (117). The crystal structure was refined to R 1 = 0.024 for 222 reflections with F > 4σ(F). It is based on lead oxide blocks derived from that of litharge PbO, which alternate with layers of chloride ions. Napoliite represents a new structure type with a unique order/disorder pattern of fluorine and oxygen atoms. The new mineral is dimorphous with rumseyite. It is named after the city of Naples (Napoli in Italian). [ABSTRACT FROM AUTHOR]

The new mineral nishanbaevite, ideally KAl2O(AsO4)(SO4), was found in sublimates of the Arsenatnaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with euchlorine, alumoklyuchevskite, langbeinite, urusovite, lammerite, lammerite-β, ericlaxmanite, kozyrevskite, and hematite. Nishanbaevite occurs as long-prismatic or lamellar crystals up to 0.03 mm typically combined in brush-like aggregates and crusts up to 1.5 mm across. It is transparent, colourless, with vitreous lustre. Dcalc = 3.012 g cm− 3. Nishanbaevite is optically biaxial (–), α = 1.552, β ≈ γ = 1.567. The chemical composition (average of seven analyses) is: Na2O 3.79, K2O 8.01, CaO 0.10, CuO 0.21, Al2O3 30.08, Fe2O3 0.50, SiO2 1.62, P2O5 0.66, As2O5 32.23, SO3 22.59, total 99.79 wt%. The empirical formula calculated based on 9 O apfu is: (K0.57Na0.41Ca0.01)Σ0.99(Al1.99Fe3+0.02Cu0.01)Σ2.02(As0.95S0.95Si0.09P0.03)Σ2.02O9. Nishanbaevite is orthorhombic, Pbcm, a = 15.487(3), b = 7.2582(16), c = 6.6014(17) Å, V = 742.1(3) Å3 and Z = 4. The strongest reflections of the powder XRD pattern [d,Å(I)(hkl)] are: 15.49(100)(100), 6.56(30)(110), 4.653(29)(111), 3.881(54)(400), 3.298(52)(002), 3.113(29)(121), and 3.038(51)(202, 411). The crystal structure, solved from single-crystal XRD data (R = 7.58%), is unique. It is based on the complex heteropolyhedral sheets formed by zig-zag chains of Al-centred polyhedra (alternating trigonal bipyramids AlO5 and octahedra AlO6 sharing edges) and isolated tetrahedra AsO4 and SO4. Adjacent chains of Al polyhedra are connected via AsO4 tetrahedra to form a heteropolyhedral double-layer. Its topological peculiarity is considered and compared with those in structurally related compounds. The (K,Na) site is located in the interlayer space between SO4 tetrahedra. The position of nishanbaevite among the arsenate-sulfates and their specific structural features are discussed. The mineral is named in honour of the Russian mineralogist Tursun Prnazorovich Nishanbaev (1955–2017). [ABSTRACT FROM AUTHOR]

Fluorpyromorphite, ideally Pb5(PO4)3F, a new apatite-group member, an F-dominant analog of pyromorphite and hydroxylpyromorphite. It is a supergene mineral found at two localities: Sukhovyaz Mountain, Ufaley District, Southern Urals (holotype) and Mountain 1004, Tolbachik volcano, Kamchatka (co-type), both in Russia. At Sukhovyaz, fluorpyromorphite forms anhedral grains up to 0.2 mm across (usually much smaller), filling cavities in quartz and sometimes partially replacing fluorapatite. Associated supergene minerals include pyromorphite, hydroxylpyromorphite, fluorphosphohedyphane, mimetite, and nickeltsumcorite. At Tolbachik, fluorpyromorphite occurs in the oxidation zone of paleo-fumarolic deposits in close association with pyromorphite, fluorphosphohedyphane, wulfenite, cerussite, munakataite, vanadinite, chrysocolla, and opal. It forms crude long-prismatic to acicular crystals up to 0.1 mm long and up to 5 μm thick combined in bunches and spherulites up to 0.2 mm. Fluorpyromorphite is colorless (Sukhovyaz) or yellow (Tolbachik), translucent to transparent and has a vitreous luster. It is brittle, with an uneven fracture and poor cleavage on (001). The calculated density values are 7.382 (holotype) and 6.831 (cotype) g/cm³. Fluorpyromorphite is optically uniaxial (-). In reflected light, it is light-grey, weakly anisotropic. The reflectance values (Rmin/Rmax, %) are: 15.8/16.6 (470 nm), 16.2/17.2 (546 nm), 15.9/16.9 (589 nm), 15.4/16.2 (650 nm). The chemical composition is (electron microprobe, wt. %; holotype/co-type): CaO 0.10/3.16, SrO 0.17/0.00, PbO 83.51/77.39, P2O5 16.13/16.35, CrO3 0.00/0.49, SeO3 0.00/0.98, F 1.00/1.35, Cl 0.29/0.40, H2Ocalc 0.13/0.00, -O=(F,Cl) -0.49/-0.66, total 100.84/99.46. The empirical formulae based on 13 anions (O + F + Cl + OH) pfu are Pb4.95Ca0.02Sr0.02P3.00O12F0.70(OH)0.19Cl0.11 (holotype) and Pb4.26Ca0.69P2.83Se6+ 0.09Cr6+0.06 O11.99F0.87Cl0.14 (co-type). Fluorpyromorphite is hexagonal, space group P63m, unit-cell parameters (from powder X-ray diffraction data; holotype / co-type) are: a = 9.779(5) / 9.732(1), c = 7.241(9) / 7.242(1) Å, V = 599.6(7) / 594.0(2) Å3, and Z = 2. The crystal structure was refined using the Rietveld method to Rp= 0.1764 (holotype). Fluorpyromorphite is isostructural with other members of the apatite group, a subdivision of the apatite supergroup. [ABSTRACT FROM AUTHOR]

The new alluaudite-group mineral khrenovite with the ideal, end-member formula Na3Fe3+2(AsO4)3 was found in the Arsenatnaya fumarole, Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with aphthitalite-group sulfates, badalovite, calciojohillerite, nickenichite, johillerite, tilasite, svabite, achyrophanite, ozerovaite, pansnerite, arsenatrotitanite, anhydrite, sanidine, hematite, cassiterite, rutile and pseudobrookite. Khrenovite occurs as coarse prismatic crystals up to 0.2 × 0.3 × 0.8 mm and their clusters up to 1 mm across. It is transparent, honey-coloured, red-, orange- or yellow-brown, with vitreous lustre. Khrenovite is brittle, cleavage was not observed. D calc is 4.257 g cm–3. Khrenovite is optically biaxial (+), α = 1.825(7), β = 1.834(7), γ = 1.845(7) and 2Vmeas. = 80(10)°. The chemical composition (wt.%, electron-microprobe) is: Na2O 11.47, K2O 1.23, CaO 0.18, MgO 0.01, MnO 4.10, CuO 4.27, ZnO 1.99, Al2O3 0.17, Fe2O3 21.12, SiO2 0.08, P2O5 0.01, V2O5 0.10, As2O5 56.03, SO3 0.02, total 100.78. The empirical formula calculated on the basis of 12 O apfu is (Na2.26K0.16Ca0.02Mn0.35Cu0.33Zn0.15Al0.02Fe3+1.62)Σ4.91(As2.98Si0.01V0.01)Σ3.00O12. Khrenovite is monoclinic, C 2/ c , a = 12.2394(7), b = 12.7967(5), c = 6.6589(4) Å, β = 112.953(7)°, V = 960.37(10) Å3 and Z = 4. The crystal structure was solved from single-crystal X-ray diffraction data with R 1 = 0.0287. Khrenovite is isostructural with other alluaudite-group minerals. Its structural formula simplified to the species-defining constituents is A(1)Na A(2)'Na M(1)Na M(2)Fe3+2(T AsO4)3. The mineral is named in honour of the Russian volcanologist and geologist Anatoly Petrovich Khrenov (1946–2016). [ABSTRACT FROM AUTHOR]

A novel solid solution between isostructural Mg arsenate and phosphate of the wagnerite group and a new As5+-rich variety of wagnerite were discovered in sublimates of the active Arsenatnaya Fumarole, Tolbachik Volcano (Kamchatka, Russia). The minerals of the wagnerite Mg2(PO4)F–arsenowagnerite Mg2(AsO4)F isomorphic series were formed by the interaction of fumarolic gas and basalt scoria under the oxidizing conditions at temperatures of >300°C. The only significant substitution in minerals of this series is As5+ ↔ P5+, with the composition of the tetrahedrally coordinated components varying within the interval of (As0.98P0.01)–(P0.54As0.42V0.01), with a gap between (As0.93P0.06) and (As0.57P0.34V0.07). Isomorphism in the tetrahedral sites (P, As5+) in wagnerite-group minerals and related natural or synthetic compounds was previously unknown. [ABSTRACT FROM AUTHOR]

Pokhodyashinite CuTlSb2(Sb1-xTlx)AsS7-x, is a new sulfosalt from the Vorontsovskoe gold deposit, Sverdlovsk Oblast', Northern Urals, Russia. It forms anhedral grains up to 0.1 × 0.05 mm in size in calcite and is associated with major orpiment, pyrite, realgar and minor baryte, clinochlore, As-bearing fluorapatite, harmotome, prehnite, native gold and a rich spectrum of sulfosalts. Pokhodyashinite is black, opaque, and has a metallic luster and a black streak. It is brittle, with an uneven fracture and poor cleavage on {100}. The Vickers hardness (VHN, 20 g load) is 55 kg/mm2, corresponding to a Mohs hardness of 2. The calculated density is 5.169 g/cm3. In reflected light, pokhodyashinite is grayish-white, bireflectance is distinct. In crossed polars, it is strongly anisotropic; rotation tints vary from dark brownish gray to light bluish-gray. No internal reflections are observed. The reflectance values for wavelengths recommended by the Commission on Ore Mineralogy of the IMA are (Rmin/Rmax, %): 28.9/34.6 (470 nm), 27.6/33.4 (546 nm), 26.7/32.4 (589 nm), 26.1/31.1 (650 nm). The empirical formula of pokhodyashinite based on ΣMe = 6 apfu is Cu0.700Ag0.340Tl1.320Pb0.020Sb2.630As0.990S6.625. Pokhodyashinite is monoclinic, space group C2/m, a = 23.431(5), b = 3.996(2), c = 14.070(3) Å, β = 110.23(3)°, V = 1236.1(8) ų and Z = 4. Its structure can be described as wavy slabs of a complex structure based on double-rods of Sb-coordination pyramids and lone-electron-pair interspaces/micelles, separated by wavy interlayers consisting of paired columns of Tl and rods of paired Cu-coordination polyhedra. A small amount of Tl-for-Sb substitution results in partial anion vacancies in one sulfur site. The new mineral is named in honor of Maxim Mikhailovitch Pokhodyashin, a pioneer of mining engineering and smelting works in the Northern Urals of the 18th century. [ABSTRACT FROM AUTHOR]

Auerbakhite (IMA 2020-047), MnTl2As2S5, is a new sulfosalt from the Vorontsovskoe gold deposit, Sverdlovsk Oblast', Northern Urals, Russia. The new mineral occurs in limestone breccias composed of calcite, dolomite, baryte, clinochlore, fluorapatite and quartz, and cemented by major realgar, orpiment and pyrite. Other minerals directly associating with auerbakhite include alabandite, bernardite, christite, cinnabar, coloradoite, dalnegroite, gillulyite, gold, hutchinsonite, imhofite, lorándite, metacinnabar, philrothite, rebulite, routhierite, sphalerite, and vrbaite. Auerbakhite forms rare and very small short-prismatic crystals and irregular grains which do not exceed 15 × 5 µm. It is transparent, has a bright red color and adamantine luster. Auerbakhite is brittle, with an uneven fracture. Cleavage is not observed. The calculated density is 5.245 g/cm³. In reflected light, auerbakhite is light gray, weakly bireflectant. In crossed polars, it is distinctly anisotropic, in light gray and brown tones, with abundant bright red internal reflections. The empirical formula of auerbakhite is Mn1.04Tl1.97Pb0.02As1.95S5.02 (based on 10 atoms pfu). Prominent features in the Raman spectrum include bands of Mn-S and As-S stretching vibrations and numerous low-frequency bands related to mixed soft modes involving bending and Tl-S stretching vibrations. Auerbakhite is orthorhombic, space group Cmce, a = 15.3280(15) Å, b = 7.662(7)Å, c = 16.6330(14)Å, V = 1953.40(18)ų and Z = 8. The crystal structure of auerbakhite was refined from the single-crystal X-ray diffraction data to R = 0.0723 for 307 observed reflections with Iobs > 3σ(I). Auerbakhite is isostructural to the synthetic phase Tl2MnAs2S5. Its crystal structure consists of complex (001) layers based on a set of MnS4 columns parallel to [010] and are composed of edge-sharing slightly irregular MnS6 octahedra. The columns are connected via Tl1 and are framed by paired AsS3 pyramids with lone electron pairs oriented into interlayer space. Highly irregular Tl(2)S6 coordination polyhedra are situated in interlayers and share ligands with the layers. The new mineral honors Russian mining engineer, manufacturer and mineralogist Alexander Andreevitch Auerbakh whose activities were closely related to Northern Urals. [ABSTRACT FROM AUTHOR]

Berezanskite, ideally Ti2□2KLi3(Si12O30), is hexagonal, space group P6/mcc, a=9.898(4), c=14.276(6) Å, V=1211.2(9) ų, Z=2. The crystal structure was refined to an R1 index of 2.08% based on 392 unique observed reflections. Berezanskite is isostructural with milarite, ideally ACa2BoCKT(2)(Be2Al)(T(1)Si12O30)(H2O)0-2. The structural unit is of the form [T(2)3T(1)12O30] with T(1)=Si and T(2)=Li, in which (LiO4) tetrahedra link [Si12O30] six-membered double-rings into a framework. The A, B and C sites occur in the interstices of the framework with the following site populations: A=Ti4+2, =1.938(2) Å; B=□2; C=K, =3.058(2) Å. In the T(2)=Li3 milarite-group minerals, the distance is inversely related to the occupancy of the B site. [ABSTRACT FROM AUTHOR]

Novel Pb7O6Br2 (1) lead oxybromide was prepared from Pb oxybromide melt by the "rapid quenching" route. Bonding scheme, thermal expansion, and structural properties were studied. The structural features of this unexpectedly complex phase are described on the basis of lone electron pair stereochemical activity and Pb-Br versus Pb-O bonding scheme. The structure of 1 contains a number of cavities, which can be assigned to the self-containments of the lone electron pairs on Pb2+ cations. "Empty" Pb4 chains are observed in between of the folding sides of the adjacent strongly corrugated oxocentered [Pb7O6]2+ layers. Highly isotropic thermal expansion of 1 appeared to be unexpected. The possible explanations of such a behavior in 1 are given. The structure of 1 is an interesting example of tetrahedral framework with mixed chemical bonding and is the densest known among Pb oxyhalides with the density of 18.4 tetrahedra/1000 ų. Current study shows that oxocentered layers derivatives from α-PbO can be very flexible and form rather dense three-dimensional structural topologies. The properties and structure are compared to other phases crystallizing in the anhydrous PbO-PbX2 (X = F, Cl, Br, I) systems, illustrate the complexity of lead oxyhalides, and reveal new and general pathways for the targeted synthesis of new phases with the Pb-O units of desired dimensionality. The indirect gap value of ~2.04 eV obtained from generalized gradient approximation calculations demonstrates potentially good photocatalytic properties of 1. [ABSTRACT FROM AUTHOR]

Metahewettite was encountered in hypergene crusts in Paleozoic carbon-silica schists included in the carbon mélange matrix at Hodzha-Rushnai-Mazar in southern Kirgizia. Schist outcrops are marked by multicolored yellow, orange, brown and green crusts of vanadates and sulfates of ehaleoalumite group, volborthite, V-bearing phosphates, Cr-V-bearing members of alunite subgroup, members of the pascoite group and vanadium-bronze oxides, including metahewettite. Metahewettite is acicular with individual crystals up to 1 mm in length, and forms radial aggregates 2-3 mm in diam-eter, or flattened aggregates in narrow fissures. Crystals are dark-brown to reddish-brown with a golden sheen. The crystal structure of metahewettite, Ca(V 5+ 6 O 16)(H 2) 3, monoclinic, a = 12.208(5), b = 3.6011(15), c = 18.358(7) Å, β = 118.538(8)°, V = 709.0(8) ų, Z = 2, A2/m, was refined to an R1, index of 2.4 % based on 1047 unique observed (Fo > 4σF) refiections. Electron-microprobe analysis (EDS) showed no detectable constituents apart from Ca and V, and the scattering from each site in the structure is conformable with the ideal composition Ca(V6,O16)(H2O) 3. There are three Fsites in the structure with scattering in accord with their complete occupancy by V. The V(1) site is [5]-coordinated by O2- anions with a distance of 1.823 Å and a [2 + 3] arrangement of vanadyl <1.67 Å> and equatorial (<1.925 Å>) bonds. The V(2) and V(3) sites are coordinated by O2- anions with distances of 1.934 and 1.916 Å and [2 + 2 + 2] and [1 + 4 + 1] arrangements of vanadyl <1.652 Å>, equatorial <1.906 Å> and tram <2.237 Å> bonds, respectively. The V(l) square pyramids share edges and vertices to form chains extending parallel to b with a repeat distance of 3.6 Å. The V(2) and V(3) octahedra share edges and vertices to form ribbons also extending parallel to b. The chains and ribbons link by sharing polyhedron comers to form sheets of V polyhedra parallel to (001). These sheets are linked by interlayer Ca that occupies two interstitial Ca sites, and by (H2-O) groups. [ABSTRACT FROM AUTHOR]

Two new minerals - manganoblödite (IMA2012-029), ideally Na2Mn(SO4)2·4H2O, and cobaltoblödite (IMA2012-059), ideally Na2Co(SO4)2·4H2O, the Mn-dominant and Co-dominant analogues of blödite, respectively, were found at the Blue Lizard mine, San Juan County, Utah, USA. They are closely associated with blödite (Mn-Co-Ni-bearing), chalcanthite, gypsum, sideronatrite, johannite, quartz and feldspar. Both new minerals occur as aggregates of anhedral grains up to 60 μm (manganoblödite) and 200 μm (cobaltoblödite) forming thin crusts covering areas up to 2 × 2 cm on the surface of other sulfates. Both new species often occur as intimate intergrowths with each other and also with Mn-Co-Ni-bearing blödite. Manganoblödite and cobaltoblödite are transparent, colourless in single grains and reddish-pink in aggregates and crusts, with a white streak and vitreous lustre. Their Mohs' hardness is ~2½. They are brittle, have uneven fracture and no obvious parting or cleavage. The measured and calculated densities are Dmeas = 2.25(2) g cm−3 and Dcalc = 2.338 g cm−3 for manganoblödite and Dmeas = 2.29(2) g cm−3 and Dcalc = 2.347 g cm−3 for cobaltoblödite. Optically both species are biaxial negative. The mean refractive indices are α = 1.493(2), β = 1.498(2) and γ = 1.501(2) for manganoblödite and α = 1.498(2), β = 1.503(2) and γ = 1.505(2) for cobaltoblödite. The chemical composition of manganoblödite (wt.%, electron-microprobe data) is: Na2O 16.94, MgO 3.29, MnO 8.80, CoO 2.96, NiO 1.34, SO3 45.39, H2O (calc.) 20.14, total 98.86. The empirical formula, calculated on the basis of 12 O a.p.f.u., is: Na1.96(Mn0.44Mg0.29Co0.14Ni0.06)Σ0.93S2.03O8·4H2O. The chemical composition of cobaltoblödite (wt.%, electron-microprobe data) is: Na2O 17.00, MgO 3.42, MnO 3.38, CoO 7.52, NiO 2.53, SO3 45.41, H2O (calc.) 20.20, total 99.46. The empirical formula, calculated on the basis of 12 O a.p.f.u., is: Na1.96(Co0.36Mg0.30Mn0.17Ni0.12)Σ 0.95S2.02O8·4H2O. Both minerals are monoclinic, space group P21/a, with a = 11.137(2), b = 8.279(1), c = 5.5381(9) Å, β = 100.42(1)°, V = 502.20(14) Å3 and Z = 2 (manganoblödite); and a = 11.147(1), b = 8.268(1), C = 5.5396(7) Å, β = 100.517(11)°, V = 501.97(10) Å3 and Z = 2 (cobaltoblödite). The strongest diffractions from X-ray powder pattern [listed as (d,Å(I)(hkl)] are for manganoblödite: 4.556(70)(210, 011); 4.266(45)(2̅01); 3.791(26)(2̅11); 3.338(21)(310); 3.291(100)(220, 021), 3.256(67)(211,1̅21), 2.968(22)(2̅21), 2.647(24)(4̅01); for cobaltoblödite: 4.551(80)(210, 011); 4.269(50)(2̅01); 3.795(18)(2̅11); 3.339(43)(310); 3.29(100)(220, 021), 3.258(58)(211, 1̅21), 2.644(21)( 4̅01), 2.296(22)( 1̅22). The crystal structures of both minerals were refined by single-crystal X-ray diffraction to R1 = 0.0459 (manganoblödite) and R1 = 0.0339 (cobaltoblödite). [ABSTRACT FROM AUTHOR]

Single crystals of the new compound Pb7O6Br2 are prepared by solid state reaction of PbBr2 and α-PbO (Pt crucible, 750 °C, 1 h). [ABSTRACT FROM AUTHOR]