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Gurzhiite, ideally Al(UO2)(SO4)2F⋅10H2O, is a new uranyl sulfate mineral from the Bykogorskoe U deposit, Northern Caucasus, Russia. It occurs as fine-grained aggregates forming veinlets up to 50 cm long in cracks of the brecciated rock. Gurzhiite aggregates are composed of small bladed crystals up to 0.1 mm across. Associated minerals include khademite and quartz. Gurzhiite is pale yellow in crystals, lemon yellow in aggregates, transparent with a vitreous lustre and a white streak. It is brittle and has an irregular fracture. Cleavage is good on {001}. The new mineral exhibits a bright yellow–green fluorescence under both longwave and shortwave UV radiation. Mohs hardness is ~2. Dmeas = 2.52(3) g/cm3 and Dcalc = 2.605 g/cm3. The mineral is biaxial (–) with α = 1.528(3), β = 1.538(2), γ = 1.544(3) (589 nm); 2Vmeas= 80(10)° and 2Vcalc = 75.1°. The empirical formula calculated on the basis of 21(O + F) atoms per formula unit (apfu) is Al0.92Zn0.05Fe3+0.03Na0.03U0.95S2.00O9.85F0.99⋅10.16H2O. Gurzhiite is triclinic, with space group P $\bar{1}$ , a = 7.193(2), b = 11.760(2), c = 11.792(2) Å, α = 67.20(3), β = 107.76(3), γ = 89.99(3)°, V = 867.7(4) Å3 and Z = 2. The five strongest lines of the powder X-ray diffraction pattern [d, Å (I, %)(hkl)] are: 10.24(100)(001); 5.40(14)($\bar{ 1}\bar{1}$ 1); 5.11(54)(002); 3.405(11)($\bar{2}$ 11); and 3.065(11)($\bar{1}\bar{1}$ 3). The crystal structure of gurzhiite is based upon uranyl sulfate chains of the same type as in bobcookite and svornostite. Between the chains are two types of Al-octahedra – Al1(H2O)6 and Al2F2(H2O)4. The entire structure stability is maintained by a complex network of H bonds. The new mineral honours Russian mineralogist and crystallographer Dr. Vladislav V. Gurzhiy in recognition for his contributions to uranium mineralogy and crystallography. [ABSTRACT FROM AUTHOR]

Plášilite (IMA 2014-021), Na(UO2)(SO4)(OH)?2H2O, is a new uranyl sulfate mineral from the Blue Lizard mine, San Juan County, Utah, USA. The new mineral occurs in and on sandstone matrix in close association with atacamite, blödite, brochantite, calcite, chalcanthite, dickite, gerhardtite, gypsum, hexahydrite, johannite, manganoblödite, natrozippeite and tamarugite. It is a low-temperature, secondary mineral formed by the post-mining weathering of uraninite. Plášilite is monoclinic, with the space group P21/c, and unit cell parameters a = 8.7122(6), b = 13.8368(4), c = 7.0465(2) Å, β = 112.126(8)°, V = 786.89(7) ų and Z = 4. Crystals are long, thin blades, elongated on [001] and flattened on {100}; rarely as prisms, also elongated on [001]. Crystals exhibit the forms {100}, {010} and {011}, and are commonly twinned on {100}. Plášilite is greenish yellow, has a white streak and fluoresces bluish white under both long-wave and short-wave UV. It is transparent with vitreous luster. The mineral has a Mohs hardness probably between 2 and 3, brittle tenacity, even fracture and two perfect cleavages, {010} and {001}. The calculated density based on the empirical formula is 3.726 g/cm³. The mineral is optically biaxial (+), with α = 1.556(1), β = 1.581(1) and γ = 1.608(1) (measured with white light). The measured 2V is 88(1)° and the calculated 2V is 89°. Dispersion is moderate, r < ν. The mineral is pleochroic with X = nearly colourless, Y = very pale yellow, Z = pale yellow; X < Y < Z. The optical orientation is X = b, Y c = 4° in obtuse β. The empirical formula of plášilite is Na0.94(UO2)(S1.01O4)(OH)(H2O)2 (based on 9 O apfu). Prominent features in the Raman spectrum include the symmetric stretching vibrations of the uranyl (UO22+) group and sulfate tetrahedra and the O-H stretching and bending vibrations of the H2O molecules. The eight strongest powder X-ray diffraction lines are [dobs Å(I )(hkl) ]: 6.90(100)(020), 5.85(99)(011,111), 4.024(57)(200,130), 3.492(82)(102,220,040), 3.136(40)(122), 2.690(25)(141,102, 241,032), 2.618(34)(240,150, 302), 1.9212(30)(mult.). The crystal structure of plášilite (R1 = 0.019 for 1603 reflections with Fobs > 4σF) contains uranyl sulfate sheets of composition [(UO2)2(SO4)2(OH)2]2- parallel to (010). Between the sheets and linking them to one another are chains of edge-sharing NaO2(H2O)4 octahedra parallel to [001]. The uranyl sulfate sheet is based on the phosphuranylite anion topology. The sheets in plášilite and deliensite are geometrical isomers. [ABSTRACT FROM AUTHOR]

Magnesioleydetite (IMA2017-063), Mg(UO2)(SO4)2·11H2O, and straβmannite (IMA2017-086), Al(UO2)(SO4)2F·16H2O, are two new minerals from mines in Red Canyon, San Juan County, Utah, USA. Magnesioleydetite occurs in the Markey mine and straβmannite occurs in both the Markey and Green Lizard mines. Both minerals are secondary phases found in efflorescent crusts on the surfaces of mine walls. Magnesioleydetite occurs in irregular aggregates (to ~0.5 mm) of blades (to ~0.2 mm) exhibiting the following properties: transparent to translucent; pale green–yellow colour; vitreous lustre; white streak; non-fluorescent; brittle; Mohs hardness ≈ 2; irregular fracture; one perfect cleavage on {001}; and calculated density = 2.463 g/cm3. Straβmannite occurs in irregular aggregates (to ~0.5 mm) of equant crystals (to ~0.2 mm) exhibiting the following properties: transparent; light yellow–green colour; vitreous to greasy lustre; nearly white streak; bright greenish-blue fluorescence; somewhat brittle, Mohs hardness ≈ 1½; irregular fracture; one good cleavage on {001}; measured and calculated densities of 2.20(2) and 2.173 g/cm3, respectively; optically biaxial (–); α = 1.477(2), β = 1.485(2) and γ = 1.489(2) (white light); 2Vmeas. = 72(2)°; dispersion r > v (slight); orientation Y = b , X ∧ c = 20° (in obtuse β); pleochroism with X = nearly colourless, Y = pale green–yellow and Z = light green–yellow (X < Y < Z). The empirical formulas for magnesioleydetite and straβmannite are (Mg0.56Fe0.26Zn0.11Mn0.01)Σ0.94(U0.99O2)(S1.015O4)2·11H2O and Al1.00Na0.16(U0.99O2)(S1.00O4)2[F0.58(OH)0.42]·16H2O, respectively. Magnesioleydetite is monoclinic, C 2/ c , a = 11.3513(3), b = 7.7310(2), c = 21.7957(15) Å, β = 102.387(7)°, V = 1868.19(16) Å3 and Z = 4. Straβmannite is monoclinic, C 2/ c , a = 11.0187(5), b = 8.3284(3), c = 26.6727(19) Å, β = 97.426(7)°, V = 2427.2(2) and Z = 4. The structures of magnesioleydetite (R 1 = 0.016 for 2040 I > 2σ I reflections) and straβmannite (R 1 = 0.0343 for 2220 I > 2σ I reflections) each contain uranyl-sulfate sheets based on the protasite-anion topology. [ABSTRACT FROM AUTHOR]

Mathesiusite, K5(UO2)4(SO4)4(VO5)(H2O)4, a new uranyl vanadate-sulfate mineral from Jáchymov, Western Bohemia, Czech Republic, occurs on fractures of gangue associated with adolfpateraite, schoepite, čejkaite, zippeite, gypsum, and a new unnamed K-UO2-SO4 mineral. It is a secondary mineral formed during post-mining processes. Mathesiusite is tetragonal, space group P4/n, with the unit-cell dimensions a = 14.9704(10), c = 6.8170(5) Å, V = 1527.78(18) ų, and Z = 2. Acicular aggregates of mathesiusite consist of prismatic crystals up to ~200 μm long and several micrometers thick. It is yellowish green with a greenish white streak and vitreous luster. The Mohs hardness is ~2. Mathesiusite is brittle with an uneven fracture and perfect cleavage on {110} and weaker on {001}. The calculated density based on the empirical formula is 4.02 g/cm3. Mathesiusite is colorless in fragments, uniaxial (-), with ω = 1.634(3) and ε = 1.597(3). Electron microprobe analyses (average of 7) provided: K2O 12.42, SO3 18.04, V2O5 4.30, UO3 61.46, H2O 3.90 (structure), total 100.12 (all in wt%). The empirical formula (based on 33 O atoms pfu) is: K4.87(U0.99O2)4(S1.04O4)4(V0.87O5)(H2O)4. The eight strongest powder X-ray diffraction lines are [dobs in Å (hkl) Irel]: 10.64 (110) 76, 7.486 (200) 9, 6.856 (001) 100, 6.237 (101) 85, 4.742 (310) 37, 3.749 (400) 27, 3.296 (401) 9, and 2.9409 (510) 17. The crystal structure of mathesiusite was solved from single-crystal X-ray diffraction data and refined to R1 = 0.0520 for 795 reflections with I > 3σ(I). It contains topologically unique heteropolyhedral sheets based on [(UO2)4(SO4)4(VO5)]5- clusters. These clusters arise from linkages between corner-sharing quartets of uranyl pentagonal bipyramids, which define a square-shaped void at the center that is occupied by V5+ cations. Each pair of uranyl pentagonal bipyramids shares two vertices of SO4 tetrahedra. Each SO4 shares a third vertex with another cluster to form the sheets. The K+ cations are located between the sheets, together with a single H2O group. The corrugated sheets are stacked perpendicular to c. These heteropolyhedral sheets are similar to those in the structures of synthetic uranyl chromates. Raman spectral data are presented confirming the presence of UO22+, SO4, and molecular H2O. [ABSTRACT FROM AUTHOR]

The new minerals klaprothite (IMA2015-087), Na6(UO2)(SO4)4(H2O)4, péligotite (IMA2015-088), Na6(UO2)(SO4)4(H2O)4 and ottohahnite (IMA2015-098), Na6(UO2)2(SO4)5(H2O)7·1.5H2O, were found in the Blue Lizard mine, San Juan County, Utah, USA, where they occur together as secondary phases. All three minerals occur as yellowish-green to greenish-yellow crystals, are brittle with irregular fracture, have Mohs hardness of ∼2½ and exhibit bright bluish-green fluorescence, and all are easily soluble in roomtemperature H2O. Only klaprothite exhibits cleavage; perfect on {100} and {001}. Quantitative energydispersive spectroscopy analyses yielded the empirical formulas Na6.01(U1.03O2)(S0.993O4)4(H2O)4, Na5.82(U1.02O2)(S1.003O4)4(H2O)4 and Na5.88(U0.99O2)2(S1.008O4)5(H2O)8.5 for klaprothite, péligotite and ottohahnite, respectively. Their Raman spectra exhibit similar features. Klaprothite is monoclinic, P21/c, a = 9.8271(4), b = 9.7452(3), c = 20.8725(15) Å, β = 98.743(7)°, V = 1975.66(17) Å3 and Z = 4. Péligotite is triclinic, P1, a = 9.81511(18), b = 9.9575(2), c = 10.6289(8) Å, α = 88.680(6)°, β = 73.990(5)°, γ = 89.205(6)°, V = 998.22(8) Å3 and Z = 2. Ottohahnite is triclinic, P1, a = 9.97562(19), b = 11.6741(2), c = 14.2903(10) Å, α = 113.518(8)°, β = 104.282(7)°, γ = 91.400(6)°, V = 1464.59(14) Å3 and Z = 2. The structures of klaprothite (R1 = 2.22%) and péligotite (R1 = 2.28%) both contain [(UO2)(SO4)4]6- clusters in which one SO4 group has a bidentate linkage with the UO7 polyhedron; Na-O polyhedra link clusters into thick heteropolyhedral layers and link layers into frameworks; the structures differ in the configuration of Na-O polyhedra that link the layers. The structure of ottohahnite (R1 = 2.65%) contains [(UO2)4(SO4)10]12- clusters in which each UO7 polyhedron has a bidentate linkage with one SO4 group; Na-O polyhedra link clusters into a thin heteropolyhedral slice and also link the slices into a framework. The minerals are named for Martin Heinrich Klaproth (1743-1817), Eugène-Melchior Péligot (1811-1890) and Otto Hahn (1879-1968). [ABSTRACT FROM AUTHOR]

The new mineral shumwayite (IMA2015-058), [(UO2)(SO4)(H2O)2]2·H2O, was found in the Green Lizard and Giveaway-Simplot mines, White Canyon district, San Juan County, Utah, USA, where it occurs as a secondary alteration phase. At the Green Lizard mine, it is found in association with calcite, gypsum, plášilite, pyrite, rozenite and sulfur; at the Giveaway-Simplot mine, shumwayite is associated with rhomboclase and römerite. The mineral occurs as pale greenish-yellow monoclinic prisms, elongated on [100], up to ~0.3 mm long and commonly in subparallel to random intergrowths. The mineral is transparent with a vitreous lustre and has a white streak. It fluoresces bright greenish white under both longwave and shortwave ultraviolet radiation. The Mohs hardness is ∼2. Crystals are brittle with perfect {011} cleavage and irregular fracture. The mineral is slightly deliquescent and is easily soluble in room temperature H2O. The calculated density is 3.844 g cm-3. Optically, shumwayite is biaxial (+/-), with α = 1.581(1), β = 1.588(1), γ = 1.595(1) (measured in white light). The measured 2Vx based on extinction data collected on a spindle stage is 89.8(8)°; the calculated 2Vx is 89.6°. Dispersion is strong, but the sense is not defined because the optic sign is ambiguous. No pleochroism was observed. The optical orientation is X = b, Y ≈ c, Z ≈ a. Energy-dispersive spectrometer analyses (with H2O based on the crystal structure) yielded the empirical formula U2.01S1.99O12.00·5H2O. Shumwayite is monoclinic, P21/c a = 6.74747(15), b = 12.5026(3), c = 16.9032(12) Å, β = 90.919(6)°, V = 1425.79(11) Å3 and Z = 4. The crystal structure (R1 = 1.88% for 2936 F > 4σF) contains UO7 pentagonal bipyramids and SO4 tetrahedra that link by corner-sharing to form [(UO2)(SO4)(H2O)2] chains along [100]. The chains and isolated H2O groups between them are linked together only by hydrogen bonds. The mineral is named in honour of the Shumway family, whose members account for the discovery and mining of hundreds of uranium deposits on the Colorado Plateau, including the Green Lizard mine. [ABSTRACT FROM AUTHOR]

The new minerals fermiite (IMA2014-068), Na4(UO2)(SO4)3·3H2O and oppenheimerite (IMA2014-073), Na2(UO2)(SO4)2·3H2O, were found in the Blue Lizard mine, San Juan County, Utah, USA, where they occur together as secondary alteration phases in association with blödite, bluelizardite, chalcanthite, epsomite, gypsum, hexahydrite, krohnkite, manganoblodite, sideronatrite, tamarugite and wetherillite. Fermiite descriptive details: pale greenish-yellow prisms; transparent; vitreous lustre; bright greenish- white fluorescence; white streak; hardness (Mohs) 2½; brittle; conchoidal fracture; no cleavage; slightly deliquescent; easily soluble in RT H2O; densitymeas = 3.23(2) g cm-3; densitycalc = 3.313 g cm-3. Optically, biaxial (+), α = 1.527(1), (β= 1.534(1), γ = 1.567(1) (white light); 2Vmeas = 51(1)°, 2Vcalc = 50°; dispersion r < v, distinct. Pleochroism: X, Y = colourless, Z = pale greenish yellow; X= Y < Z. Energy dispersive spectroscopic (EDS) analyses yielded the empirical formula Na3.88(U1.05O2)(S0.99O4)3(H2O)3. Fermiite is orthorhombic, Pmn21, a = 11.8407(12), b = 7.8695(5), c = 15.3255(19) Å, V= 1428.0(2) Å3 and Z = 4. The structure (R1 = 2.21% for 1951 Io > 3σl) contains [(UO2)(SO4)3] chains that are linked by bonds involving five different Na-O polyhedra to form a framework. The mineral is named for Italian-American theoretical and experimental physicist Dr. Enrico Fermi (1901-1954). Oppenheimerite descriptive details: pale greenish-yellow prisms; transparent; vitreous lustre; bright greenish-white fluorescence; white streak; hardness (Mohs) 2½; slightly sectile; three good cleavages, {11̅0}, {011} and {101}; irregular fracture; slightly deliquescent; easily soluble in RT H2O; densitycalc = 3.360 g cm-3. Optically, biaxial (+), α = 1.537(1), β = 1.555(1), y = 1.594(1) (white light); 2Vmeas. = 72(2)°, 2Vcalc = 70°; dispersion is r > v, moderate, inclined; optical orientation: X ≈ ⊥ {101}, Z ≈ [111̅]; pleochroism: X very pale greenish yellow, Y pale greenish yellow, Z greenish yellow; X < Y < Z. EDS analyses yielded the empirical formula Na1.94(U0.97O2)(S1.02O4)2(H2O)3. Oppenheimerite is triclinic, P1̅, a = 7.9576(6), 6 = 8.1952(6), c = 9.8051 (7) Å, α = 65.967(5)' β = 70.281 (5), y = 84.516(6)°, V= 549.10(8) Å3 and Z = 2. The structure (Rx = 3.07% for 2337 I0 > 3σI) contains [(UO2)(SO4)2(H2O)] chains that are linked by bonds involving two different Na-O polyhedra to form a framework. The mineral is named for American theoretical physicist Dr. J. Robert Oppenheimer (1904-1967). [ABSTRACT FROM AUTHOR]

Svornostite (IMA2014-078), K2Mg[(UO2)(SO4)2]2·8H2O, is a new uranyl sulfate mineral from Jáchymov, Western Bohemia, Czech Republic. The new mineral was found in material originating from the Geschieber vein in the Svornost mine. It occurs as crystalline crusts composed of yellow prismatic crystals on a gangue along with geschieberite, adolfpateraite and gypsum. It is a low-temperature, supergene mineral formed by the post-mining weathering of uraninite. Svornostite is orthorhombic, the space group Pmn21, with the unit-cell parameters a = 12.7850(3), b = 8.2683(4), c = 11.2163(3) Å, V = 1185.68(7) ų and Z = 2. Crystals are long prisms elongated on [001] and flattened on {100}. Crystals exhibit the forms {100}, {010} and {011}, usually forming multiple intergrowths. Svornostite is light yellow and has a very pale yellow streak. It exhibits a strong yellowish-green fluorescence under both long-wave and short-wave UV. It is translucent to transparent with strong vitreous luster. The mineral has a Mohs hardness ~2; it is brittle, with uneven fracture and a perfect cleavage, on {100} and {010}. The calculated density based on the empirical formula is 3.268 g/cm³. The mineral is optically biaxial (+), with α = 1.548(2), β = 1.556(3) and γ = 1.585(2) (measured at 590 nm). The 2V was not measured, calculated value is 56°. Birefringence is 0.037. No dispersion or pleochroism was observed. The optical orientation is Z = c. Chemical analysis (EDS, 6 spots) is K2O 7.93, MgO 3.11, CuO 0.79, SO3 28.13, UO3 48.94, H2O (calc.) 12.53, total 101.43 wt. %, which yields the empirical formula K1.94(Mg0.89Cu0.11)S1.00(U0.99O2)2(S1.01O4)4(H2O)8 (based on 28 O apfu). Prominent features in the Raman spectrum include the O-H stretching vibrations, symmetric stretching vibrations of (UO2)2+ ion, and stretching and bending vibrations of symmetrically non-equivalent SO4 groups. The eight strongest powder X-ray diffraction lines are [dobs Å (Irel.) (hkl)]: 8.279(50)(010), 6.398(100)(200), 5.060(55)(210), 4.645(40)(012), 4.610(38)(211), 3.881(34)(021), 3.318(44)(221), 3.009(44)(213). The crystal structure of svornostite (R = 0.023 for 2745 reflections with Iobs > 3σ[I]) contains infinite uranyl sulfate chains of composition [(UO2)(SO4)2(H2O)]2- parallel to (001). The adjacent chains are linked through the Mg2+-octahedra linked to the apical O atoms of the SO4 groups with the chains and additionally by the K-O bonds and also H-bonds involving H2O molecules. The uranyl sulfate chains are the same as found in the structures of several others uranyl sulfate minerals. [ABSTRACT FROM AUTHOR]

Bluelizardite (IMA2013-062), Na7(UO2)(SO4)4Cl(H2O) 2, is a new uranyl sulfate mineral from the Blue Lizard mine, San Juan County, Utah (USA). It was found in a sandstone matrix and is associated with chalcanthite, copiapite, ferrinatrite, gypsum, krohnkite, johannite, and several other new, unnamed Na- and Mg-containing uranyl sulfates. Bluelizardite is a supergene mineral formed by the post-mining weathering of uraninite. The mineral is monoclinic, Cllc, with a = 21.1507(6), b = 5.3469(12), c = 34.6711(9) Å, β = 104.913(3)°, V= 3788.91(17) ų and Z= 8. Crystals are blades up to 0.4 mm long, flattened on {001}, elongated parallel to [010] and exhibiting the forms {100}, {001} and {111}. Bluelizardite is pale yellow and has a yellowish-white streak. It has good cleavage on {001} and uneven fracture. The Mohs hardness is estimated at 2. The calculated density based on the empirical formula is 3.116 g/cm³. Bluelizardite exhibits bright yellow-green fluorescence under both long- and short-wave UV radiation. The mineral is optically biaxial (--), with α = 1.515(1), β = 1.540(1) and γ = 1.545(1) (measured with white light). The measured 2Fis 48(2)° and the calculated 2Kis 47.6°. The mineral does not exhibit any dispersion or pleochroism. The optical orientation is X= b, Y ≈ a, Z ≈ c*. The empirical formula of bluelizardite is Na6.94(U1.02O2)(SO4)4.00Cl0.94O0.06 (H2O) 2 (based on 21 anions pfu). The Raman spectrum is dominated by the symmetric stretching vibrations ofthe uranyl (UO22+) group and sulfate tetrahedra and by the O-H stretching and bending vibrations ofthe H2O molecules. The eight strongest powder X-ray diffraction lines are [dobs Å(I)(hkl) ]: 17.08(52)(002), 10.31(60)(200), 5.16(100)(mult.), 4.569(22)(402,-114), 4.238(23)(-115, 310, 008), 3.484(27)(-602,-604,-2-0-10), 3.353(28)(mult.), 3.186(36)(mult.). The crystal stmcture of bluelizardite (R1 = 0.016 for 4268 reflections with Iobs > 3σI) is topologically unique among known structures of uranyl minerals and inorganic compounds. It is based upon clusters of uranyl pentagonal bipyramids and sulfate tetrahedra. Two uranyl pentagonal bipyramids are linked through the two vertices of SO4 groups. The remaining three vertices of each UO7 bipyramid are occupied by SO4 groups, linked monodentately. The eight independent Na+ cations are linked through the Na-O bonds along with hydrogen bonds (involving H...O and H...Cl bonds) into a 3D framework. [ABSTRACT FROM AUTHOR]