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The new mineral bobfinchite (IMA2020-082), Na[(UO2)8O3(OH)11]·10H2O, was found in the Burro mine, Slick Rock district, San Miguel County, Colorado, U.S.A., where it occurs as an oxidation product of uraninite on asphaltite matrix in intimate association with gypsum, natrozippeite, metaschoepite, and uranopilite. Bobfinchite crystals are transparent to translucent, yellow, lozenge-shaped disks up to 0.3 mm wide. Crystals are flattened on [100] and exhibit the forms {100}, {011}, {021}, {0 2 1}, and {0 1 1}. Bobfinchite has a pale-yellow streak and emits very dim yellow fluorescence under 365 nm ultraviolet illumination. The crystals are brittle with very good {100} cleavage and irregular, stepped fracture. The Mohs hardness is ca. 2 based on scratch tests. The calculated density is 5.044 g/cm3 based on the empirical formula and 5.036 g/cm3 for the ideal formula. Bobfinchite is optically biaxial (–), with α = 1.690(5), β = 1.7205(5), and γ = 1.730(5) (white light). The measured 2V, estimated from the interference figure, is 55(5)° and the calculated value is 59.1°. Dispersion is moderate, r > ν; orientation: X = a, Y = b, Z = c; pleochroism: X nearly colorless, Y yellow, Z yellow; X < Y ≈Z. Electron microprobe analysis provided the empirical formula (Na0.99Pb0.02)[(UO2)7.99O3(OH)11]·10H2O. The five strongest X-ray powder diffraction lines are [dobs in Å(I)(hkl)]: 7.34(100)(200), 3.59(50)(024), 3.23(60)(224), 3.18(36)(240), and 2.01(23)(624,551,208,640,346). Bobfinchite is orthorhombic, Pbcn, a = 14.6249(9), b = 14.0389(10), c = 16.6923(10) Å, V = 3427.2(4) Å3, and Z = 4. The structure of bobfinchite (R1 = 0.0330 for 3770 I > 4σI) is built from uranyl oxide-hydroxide sheets that adopt the fourmarierite topology, with interlayer Na+ and H2O groups. Both the sheet and interlayer topology mimic those observed in natural and synthetic Na-metaschoepites studied previously, and as seen in other uranyl oxide hydrate minerals, charge balance is achieved at specific sites in the sheet through the substitution O2– ↔ (OH)–. [ABSTRACT FROM AUTHOR]

Cuprozheshengite, Pb4CuZn2(AsO4)2(PO4)2(OH)2, is a new mineral species from Yunnan, China. It occurs as sub-millimeter greenish-blue hemispherical aggregates of microscopic blade-like crystals on hemimorphite and is closely associated with veszelyite and galena. Cuprozheshengite is brittle with irregular fracture and has a Mohs hardness of 2½–3 and perfect cleavages on {011}. The calculated density is 5.91 g/cm3. The empirical chemical formula of the holotype is (Pb3.97Na0.04Ca0.01)Σ4.02Cu1.06 Zn2.09(AsO4)2[(P0.84As0.12Si0.01)Σ0.97O4]2(OH)2 based on 18 O atoms per formula unit. Cuprozheshengite is triclinic, space group P 1 , with unit-cell parameters a = 4.7977(8), b = 8.5789(8), c = 10.3855(9) Å, α = 97.270(8)°, β = 101.902(12)°, γ = 91.495(11)°, V = 414.30(9) Å3, and Z = 1. Cuprozheshengite is a member of dongchuanite group, whose general formula is A4VIBIVB2(X1O4)2(X2O4)2(OH)2, where A is an interlayer cation with Pb being dominant; B are transition metals with two crystallographic positions, IVB has tetrahedral coordination and is fully occupied by Zn, while VIB has octahedral coordination and is dominated by Zn or Cu; X1 and X2 are cations with tetrahedral coordination, occupied by As and P. Like other dongchuanite group minerals, the structural framework of cuprozheshengite is composed of two heteropolyhedral columns along [100]. Type 1 columns comprise corner-linked [IVBO4] and [X2O4] tetrahedra. Each tetrahedron is connected with three other tetrahedra in the columns. Type 2 columns have alternating [VIBO4(OH)2] octahedra with pairs of corner-connected [X1O4] tetrahedra. These two columns are connected by corner-sharing between [IVBO4] and [X1O4] tetrahedra to form layers parallel to (011). Pb atoms occupy two independent sites between the layers. Cuprozheshengite is named as the copper analog of zheshengite. Single-crystal X-ray diffraction reveals that As and P order over the X1 and X2 sites, with As tending to occupy X1. Density functional theory (DFT) calculations confirm the occupancy propensity of As benefiting structural stability. The structural and stability studies of cuprozheshengite may have implications for local environmental governance. As a stable mineral in the water and elemental cycles after weathering, cuprozheshengite still has the potential to continually crystallize, fixing As into a stable crystalline waste form. [ABSTRACT FROM AUTHOR]

Waipouaite, Ca3 (V 4.5 4 + V 0.5 5 + ) O9[(Si2O5(OH)2][Si3O7.5(OH)1.5]·11H2O, is a new mineral from the Aranga Quarry, Northland Region, New Zealand. It occurs in basalt as overgrowths on thompsonite-Ca and chabazite-Ca and as inclusions within calcite and okenite. It forms dark olive green to almost black prismatic crystals to 0.3 mm in length. Crystals are transparent to translucent with a vitreous luster. The Mohs hardness is ~2, and the measured density is 2.24(2) g/cm3. The new mineral is biaxial (+), with α = 1.620(5), β = 1.622(5), γ = 1.628(5) (white light). The calculated 2V is 60.2°. Dispersion could not be observed. The optical orientation is Z = b. Pleochroism is X blue-green, Y olive green, Z olive; X > Y >> Z. Electron microprobe analyses gave the empirical formula (based on 36 O apfu) (Ca2.90Na0.05K0.04Sr0.01)Σ3.00 (V 4.60 4 + V 0.44 5 + ) Σ 5.04 (Si4.97Al0.02)Σ4.99O21.45OH3.55·H2O11.00. Waipouaite is monoclinic, P21/c, a = 12.843(3), b = 23.589(5), c = 11.560(2) Å, β = 115.54(3)°, V = 3160.0(13) Å3, and Z = 4. The eight strongest reflections in the X-ray powder diffraction pattern are [dobs in Å (I) (hkl)]: 11.78 (100) (020, 100), 9.54 (16) (011), 7.85 (19) (021), 6.29 (32) (031), 5.92 (31) (040), 5.22 (21) (1 22), 3.140 (18) (3 33), 2.850 (17) (180, 242). The crystal structure was refined using synchrotron single-crystal X-ray data to R1 = 6.85% for 6594 reflections with I>2σI. Waipouaite is the first natural polyoxovanadosilicate and has a novel structure based on [(V4+,V5+)5OI7] polyoxovanadate units, which are unique in natural and synthetic phases. Synthesis of polyoxovanadosilicates has proved to be a great challenge, and the discovery of waipouaite demonstrates that these compounds can form under natural conditions. [ABSTRACT FROM AUTHOR]

Plumboperloffite, PbMn2+2Fe3+2(PO4)3(OH)3, is a new mineral and member of the bjarebyite group from Wiperaminga Hill West Quarry, Boolcoomatta Reserve, Olary Province, South Australia, Australia. The mineral was found in a single cavity in triplite–barbosalite matrix associated with fluorapatite, phosphosiderite, natrodufrénite and fluorite. The mineral forms intergrowths of subparallel, thin tabular to bladed crystals. Individual crystals are up to 40 μm in length. Plumboperloffite is brownish orange in colour with a vitreous lustre. The mineral has brittle tenacity, an excellent cleavage on {100} and uneven fracture. The calculated density is 4.416 g/cm3. Plumboperloffite is biaxial (+), α = 1.87(1), β = 1.88(1) and γ = 1.89(1) as measured in white light. The measured 2V is 88(1)°. Dispersion is apparently strong, based on extinction colours and the orientation is Y = b. The pleochroism in shades of yellow brown is X < Z < Y. Electron microprobe analysis gave the empirical formula (based on 15 O apfu) (Pb0.92Ca0.04Ba0.01K0.01)Σ0.98(Mn2+1.84Fe2+0.13)Σ1.97(Fe3+1.97Al0.03)Σ2.00(P3.01O11.94)(OH)Σ3.06. Plumboperloffite is monoclinic, space group P 21/ m with a = 9.1765(18), b = 12.340(3), c = 5.0092(10) Å, β = 101.01(3)°, V = 556.8(2) Å3 and Z = 2. The crystal structure has been refined using X-ray single-crystal data to a final R 1 = 0.0207 on the basis of 1417 reflections with F o > 4σ(F o). The mineral is isostructural with members of the bjarebyite-group minerals. [ABSTRACT FROM AUTHOR]

The new mineral naalasite (IMA2023–027), NaAl(AsO3OH)2⋅H2O, was found at the Torrecillas mine, Iquique Province, Chile, where it is a secondary alteration phase associated with anhydrite, juansilvaite, magnesiokoritnigite and a lavendulan-like phase. Naalasite occurs in tightly intergrown aggregates and druses of equant crystals. Crystals are light to medium pink and transparent, with vitreous lustre and white streak. The Mohs hardness is ~3½. The density is 3.19(2) g⋅cm–3. Optically, naalasite is uniaxial (+), with ω = 1.630(3) and ɛ = 1.660(3) (white light). The empirical formula (based on 9 O apfu) is Na0.92Al0.61Fe3+0.39As2O9H4.07. Naalasite is trigonal, space group R 32, with cell parameters: a = 8.494(4), c = 26.430(13) Å, V = 1651.5(4) Å3 and Z = 9. The structure, refined to R 1 = 3.78% for 641 I > 2σ I reflections, is based on a loose 3D framework of alternating AsO3OH tetrahedra and AlO6 octahedra. The structure is topologically equivalent to that of nafeasite and can be regarded as its Al analogue, even though nafeasite is monoclinic with space group C 2. [ABSTRACT FROM AUTHOR]

Bimbowrieite, NaMgFe3+5(PO4)4(OH)6⋅2H2O, is a new mineral found in a mineralogically zoned rare-element bearing pegmatite at the White Rock No.2 quarry, Bimbowrie Conservation Park, South Australia, Australia. Crystals are dark olive green to greenish brown and are bladed with dimensions of up to 150 μm. Crystals occur as aggregates up to 0.4 mm across associated with ushkovite, bermanite, leucophosphite and sellaite. Bimbowrieite is pleochroic, biaxial (+), with α = 1.785(5), β = 1.795(5), γ = 1.805(5) and 2V(meas.) = 89.4(5)°. The average of 28 chemical analyses gave the empirical formula: (Na0.81Ca0.19)Σ1.00(Mg0.75Mn2+0.19Fe2+0.05)Σ0.99(Fe3+4.99Al0.01)Σ5.00(PO4)3.97(OH)5.88⋅2.05 H2O based on 24 oxygen atoms. Bimbowrieite is monoclinic, space group C 2/c with a = 25.944(5), b = 5.1426(10), c = 13.870(3 Å, β = 111.60(3)°, V = 1720.4(7) Å3 and Z = 4. The crystal structure was refined to R 1 = 1.97% for 1060 observed reflections with F 0 > 4σ(F 0). Bimbowrieite is isostructural with dufrénite. The structure is based on a trimer of face-sharing octahedra in which an M 2 octahedra shares two trans faces with two M 4 octahedra. Trimers link in the c -direction by sharing corners with two M 3 octahedra and with T 1 and T 2 tetrahedra. Linkage in the a -direction is via corner-sharing M 1 octahedra and linkage in the b -direction is via corner-sharing T 1 and T 2 tetrahedra. [ABSTRACT FROM AUTHOR]

The new mineral désorite, Pb2(Fe3+6Zn)O2(PO4)4(OH)8, is a secondary oxidation-zone mineral discovered on the dumps of the Schöne Aussicht mine, Dernbach, Westerwaldkreis, Rhineland-Palatinate, Germany. The crystals are irregular blades up to about 0.25 mm long, occurring in subparallel and radial aggregates. Désorite is brownish red. It has an orange streak, adamantine luster, brittle tenacity, splintery and curved fracture and two cleavages: {02 1 ¯ } perfect and {001} good. It has a hardness (Mohs) of about 3 and is nonfluorescent in both long- and short-wave ultraviolet illumination. The calculated density is 4.633 g/cm3. Optically, crystals are biaxial (+) with α = 2.00(1), β = 2.02(calc) and γ = 2.10(calc) (white light). The 2V is 54(2)° and the optical orientation is Y ~⊥{02 1 ¯ }, X ∧ a ≈ 13°. The mineral is pleochroic: X yellow brown, Y red brown, Z red brown; X < Y ≈ Z. The empirical formula from electron microprobe analysis is Pb1.93(Zn0.50Fe3+6.29☐0.21)Σ7.00(P3.90As0.10)Σ4.00O26H8.28. Désorite is triclinic, space group P 1 ¯ ; the unit-cell parameters are a = 5.4389(7), b = 9.3242(13), c = 10.0927(12) Å, α = 109.024(8), β = 90.521(6), γ = 97.588(7)°, V = 478.90(11) Å3 and Z = 1. Désorite has a framework structure (R1 = 0.0487 for 937 I > 2σI reflections) assembled from Fe3+O6 octahedra and PO4 tetrahedra, with Pb occupying cavities in the framework. The Fe3+O6 octahedra in the framework occur in edge-sharing chains, edge-sharing trimers and individual octahedra, all sharing corners with each other and with PO4 tetrahedra. Désorite is isostructural with jamesite and lulzacite. [ABSTRACT FROM AUTHOR]

The new mineral libbyite (IMA2022-091), (NH4)2(Na2□)[(UO2)2(SO4)3(H2O)]2⋅7H2O, was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as tightly intergrown aggregates of light green–yellow equant crystals in a secondary assemblage with bobcookite, coquimbite, halotrichite, metavoltine, rhomboclase, römerite, tamarugite, voltaite and zincorietveldite. The streak is very pale green yellow and the fluorescence is strong green under 405 nm ultraviolet light. Crystals are transparent with vitreous lustre. The tenacity is brittle, the Mohs hardness is ~2½, the fracture is curved. The mineral is soluble in H2O and has a calculated density of 3.465 g⋅cm–3. The mineral is optically uniaxial (–) with ω = 1.581(2) and ɛ = 1.540(2). Electron microprobe analyses provided (NH4)1.92K0.08Na2.00U4.00S6.00O41H18.00. Libbyite is tetragonal, P 41212, a = 10.7037(11), c = 31.824(2) Å, V = 3646.0(8) Å3 and Z = 4. The structural unit is a uranyl–sulfate sheet that has the same topology as the sheets in several synthetic uranyl selenates. [ABSTRACT FROM AUTHOR]

The new mineral zincorietveldite (IMA2022-070), Zn(UO2)(SO4)2(H2O)5, was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as yellow to orange–yellow blades in a secondary assemblage with bobcookite, coquimbite, halotrichite, libbyite, metavoltine, rhomboclase, römerite, tamarugite and voltaite. The streak is very pale yellow. Crystals are transparent with vitreous lustre. The tenacity is brittle, the Mohs hardness is ~2½ and the fracture is curved. Cleavage is excellent on {010}, good on {100} and fair on {001}. The mineral is easily soluble in H2O and has a calculated density of 3.376 g⋅cm–3. The mineral is optically biaxial (+) with α = 1.568(2), β = 1.577(2) and γ = 1.595(2); 2V = 70(1)°. Electron microprobe analyses provided (Zn0.720Mg0.109Fe0.091Mn0.046Co0.035)Σ1.00(UO2)(SO4)2(H2O)5. Zincorietveldite is orthorhombic, Pmn 21, a = 12.8712(9), b = 8.3148(4), c = 11.2959(4) Å, V = 1208.90(11) Å3 and Z = 4. Zincorietveldite is the Zn analogue of rietveldite. The structural unit is a uranyl-sulfate chain that is also found in the structures of bobcookite, oldsite, oppenheimerite and svornostite. [ABSTRACT FROM AUTHOR]