ALBERT

Description: 〈div data-abstract-type="normal"〉〈p〉Magnesioleydetite (IMA2017-063), Mg(UO〈span〉2〈/span〉)(SO〈span〉4〈/span〉)〈span〉2〈/span〉·11H〈span〉2〈/span〉O, and straβmannite (IMA2017-086), Al(UO〈span〉2〈/span〉)(SO〈span〉4〈/span〉)〈span〉2〈/span〉F·16H〈span〉2〈/span〉O, 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/cm〈span〉3〈/span〉. 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/cm〈span〉3〈/span〉, respectively; optically biaxial (–); α = 1.477(2), β = 1.485(2) and γ = 1.489(2) (white light); 2V〈span〉meas.〈/span〉 = 72(2)°; dispersion 〈span〉r〈/span〉 〉 〈span〉v〈/span〉 (slight); orientation 〈span〉Y〈/span〉 = 〈span〉b〈/span〉, 〈span〉X〈/span〉 ∧ 〈span〉c〈/span〉 = 20° (in obtuse β); pleochroism with 〈span〉X〈/span〉 = nearly colourless, 〈span〉Y〈/span〉 = pale green–yellow and 〈span〉Z〈/span〉 = light green–yellow (〈span〉X〈/span〉 Y Z). The empirical formulas for magnesioleydetite and straβmannite are (Mg〈span〉0.56〈/span〉Fe〈span〉0.26〈/span〉Zn〈span〉0.11〈/span〉Mn〈span〉0.01〈/span〉)〈span〉Σ0.94〈/span〉(U〈span〉0.99〈/span〉O〈span〉2〈/span〉)(S〈span〉1.015〈/span〉O〈span〉4〈/span〉)〈span〉2〈/span〉·11H〈span〉2〈/span〉O and Al〈span〉1.00〈/span〉Na〈span〉0.16〈/span〉(U〈span〉0.99〈/span〉O〈span〉2〈/span〉)(S〈span〉1.00〈/span〉O〈span〉4〈/span〉)〈span〉2〈/span〉[F〈span〉0.58〈/span〉(OH)〈span〉0.42〈/span〉]·16H〈span〉2〈/span〉O, respectively. Magnesioleydetite is monoclinic, 〈span〉C〈/span〉2/〈span〉c〈/span〉, 〈span〉a〈/span〉 = 11.3513(3), 〈span〉b〈/span〉 = 7.7310(2), 〈span〉c〈/span〉 = 21.7957(15) Å, β = 102.387(7)°, 〈span〉V〈/span〉 = 1868.19(16) Å〈span〉3〈/span〉 and 〈span〉Z〈/span〉 = 4. Straβmannite is monoclinic, 〈span〉C〈/span〉2/〈span〉c〈/span〉, 〈span〉a〈/span〉 = 11.0187(5), 〈span〉b〈/span〉 = 8.3284(3), 〈span〉c〈/span〉 = 26.6727(19) Å, β = 97.426(7)°, 〈span〉V〈/span〉 = 2427.2(2) and 〈span〉Z〈/span〉 = 4. The structures of magnesioleydetite (〈span〉R〈/span〉〈span〉1〈/span〉 = 0.016 for 2040 〈span〉I〈/span〉 〉 2σ〈span〉I〈/span〉 reflections) and straβmannite (〈span〉R〈/span〉〈span〉1〈/span〉 = 0.0343 for 2220 〈span〉I〈/span〉 〉 2σ〈span〉I〈/span〉 reflections) each contain uranyl-sulfate sheets based on the protasite-anion topology.〈/p〉〈/div〉

Description: 〈div data-abstract-type="normal"〉〈p〉The new mineral ammoniomathesiusite (NH〈span〉4〈/span〉)〈span〉5〈/span〉(UO〈span〉2〈/span〉)〈span〉4〈/span〉(SO〈span〉4〈/span〉)〈span〉4〈/span〉(VO〈span〉5〈/span〉)·4H〈span〉2〈/span〉O, was found in the Burro mine, San Miguel County, Utah, USA, where it occurs as a secondary phase on asphaltum/quartz matrix in association with ammoniozippeite, gypsum, jarosite and natrozippeite. The mineral forms pale yellow to greenish-yellow prisms, up to ~0.3 mm long, with pale-yellow streak and bright yellow–green fluorescence. Crystals are transparent and have vitreous lustre. The mineral is brittle, with Mohs hardness of 2½, stepped fracture and two cleavages: excellent on {110} and good on {001}. The calculated density is 3.672 g/cm〈span〉3〈/span〉. Ammoniomathesiusite is optically uniaxial (–) with ω = 1.653(2) and ε = 1.609(2) (white light). Pleochroism is: 〈span〉O〈/span〉 = green-yellow, 〈span〉E〈/span〉 = colourless; 〈span〉O〈/span〉 〉 〈span〉E〈/span〉. Electron microprobe analyses yielded the empirical formula [(NH〈span〉4〈/span〉)〈span〉4.75〈/span〉(UO〈span〉2〈/span〉)〈span〉4〈/span〉(SO〈span〉4〈/span〉)〈span〉4〈/span〉(VO〈span〉5〈/span〉)·4(H〈span〉2.07〈/span〉O). The five strongest powder X-ray diffraction lines are [〈span〉d〈/span〉〈span〉obs〈/span〉 Å(〈span〉I〈/span〉)(〈span〉hkl〈/span〉)]: 10.57(46)(110), 7.10(62)(001), 6.41(100)(101), 3.340(35)(240) and 3.226(44)(141). Ammoniomathesiusite is tetragonal, 〈span〉P〈/span〉4/〈span〉n〈/span〉 with 〈span〉a〈/span〉 = 14.9405(9), 〈span〉c〈/span〉 = 7.1020(5) Å, 〈span〉V〈/span〉 = 1585.3(2) Å〈span〉3〈/span〉 and 〈span〉Z〈/span〉 = 2. The structure of ammoniomathesiusite (〈span〉R〈/span〉〈span〉1〈/span〉 = 0.0218 for 3427 〈span〉I〈/span〉 〉 2σ〈span〉I〈/span〉) contains heteropolyhedral sheets based on [(UO〈span〉2〈/span〉)〈span〉4〈/span〉(SO〈span〉4〈/span〉)〈span〉4〈/span〉(VO〈span〉5〈/span〉)]〈span〉5–〈/span〉 clusters. The structure is identical to that of mathesiusite, with 〈span〉〈span〉〈img data-mimesubtype="gif" data-type="simple" src="http://static.cambridge.org/resource/id/urn:cambridge.org:id:binary:20190313104343836-0311:S0026461X18001123:S0026461X18001123_inline1.gif"〉 〈span data-mathjax-type="texmath"〉 〈/span〉 〈/span〉〈/span〉 in place of K〈span〉+〈/span〉.〈/p〉〈/div〉

Description: Ferroericssonite, ideally BaFe2+ 2Fe3+(Si2O7)O(OH), is a new mineral species found at both the Esquire #7 and #8 claims, situated along Big Creek in eastern Fresno County, and also at Trumbull Peak in Mariposa County, California, U.S.A. The mineral is the Fe2+ analogue of ericssonite and is named accordingly. Ferroericssonite crystallized very late in a sequence of minerals resulting from fluids interacting with a quartz-sanbornite vein along its margin with the country rock. It is closely associated with anandite, bazirite, celsian, devitoite, quartz and titantaramellite. The crystals occur in dark reddish brown foliated masses of irregular, undulating striated blades up to several mm in length, flattened on {100} and elongate and striated parallel to [001]. The mineral is transparent and has a brown streak, a vitreous luster, a Mohs hardness of approximately 4[1/2], and two cleavages: {100} perfect and {011} good. It is brittle with an irregular fracture. The calculated densities are 4.445 and 4.413 g/cm3 on the basis of the empirical formulas for Esquire #7 and Esquire #8 material, respectively. It is optically biaxial (+), {alpha} 1.827(3), {beta} 1.845(3), {gamma} 1.920(6) (white light); 2Vmeas = 63(2){degrees}; 2Vcalc = 63.0{degrees}; parallel dispersion, r 〈 v; orientation: X = b, Y {approx} c, Z {approx} a; pleochroic: brown, Z 〉 X 〉 Y. Electron-microprobe analyses of Esquire #7 and Esquire #8 material provided: BaO 30.11, 29.76, MgO 0.21, 0.10, MnO 1.19, 0.79, FeO 26.01, 26.24, Fe2O3 15.30, 15.35, Al2O3 0.02, 0.04, SiO2 22.89, 23.34, F 0.09, 0.05, Cl 1.29, 0.88, H2O 1.33, 1.42, F + Cl{equiv} O -0.33, -0.22, total 98.11, 97.75 wt%, with FeO and Fe2O3 assignments and H2O based on the structure. The empirical formulas for Esquire #7 and Esquire #8 material, based on Mg + Fe + Mn + Si = 5 apfu, are Ba1.02(Fe2+1.89Mn2+ 0.09Mg0.03){sum}2.01Fe3+ 1.00(Si1.99O7)O[(OH)0.77O0.02Cl0.19F0.02]{sum}1 and Ba1.01(Fe2+1.90Mn2+0.06 Mg0.01){sum}1.97Fe3+1.00(Si2.02O7)O[(OH)0.82O0.04Cl0.13F0.01]{sum}1, respectively. Ferroericssonite is monoclinic, C2/m, a 20.3459(10), b 7.0119(3), c 5.3879(4) A, {beta} 94.874(7){degrees}, V 765.89(7) A3 and Z = 4. The strongest five lines in the X-ray powder-diffraction pattern [dobs in A(I)(hkl)] are: 3.708(42)([IMG]f1.gif" ALT="Formula" BORDER="0"〉11), 3.506(81)(311, 510, 020), 2.880(42)(420), 2.788(100)(221) and 2.663(83)( [IMG]f2.gif" ALT="Formula" BORDER="0"〉02, 710). The crystal-structure determination (R1 = 3.56% for 885 Fo 〉 4{sigma}F) shows the mineral to be a heterophyllosilicate with a Fe2+ trioctahedral (O) sheet flanked on either side by heterophyllosilicate (H) layers, forming a HOH composite sheet. The heterophyllosilicate layers are composed of Si2O7 groups linked by Fe3+ square pyramids in a configuration referred to as a TS (Ti silicate) block, although five-coordinated Fe3+ takes the place of Ti4+. The region between the composite sheets is occupied by Ba2+. Ferroericssonite is a member of the lamprophyllite group.

Description: Rakovanite, Na3{H3[V10O28]}{middle dot}15H2O, is a new mineral species from the Sunday and the West Sunday mines, Slick Rock district, San Miguel County, Colorado, USA; the mineral is the natural analog of the previously synthesized phase. Rakovanite is orange, with an orange-yellow streak. Crystals of rakovanite are up to 1 mm in maximum dimension and vary in habit from blocky to prismatic on [100]. The mineral is transparent, with a subadamantine luster; it does not fluoresce in long- or short-wave ultraviolet radiation. Rakovanite displays brittle tenacity, and has a Mohs hardness of 1. No cleavage or parting was observed, and the mineral displays a conchoidal fracture. The density calculated from the ideal formula and the single-crystal cell data is 2.407 g cm-3. Rakovanite is biaxial (+), with {alpha}589nm = 1.776(5), {beta}589nm = 1.803(5), {gamma}589nm = 1.910(6). The measured values of 2V are: 2Vz540nm = 58(1); 2Vz589nm = 56(1); 2Vz650nm = 53(1){degrees}. Dispersion is r 〈 v, strong, parallel; orientation: X = b; Z / c = 8{degrees} in obtuse {beta}. The pleochroic scheme in rakovanite is: X light yellow, Y orangish yellow, Z yellowish orange, Z 〉 Y 〉 X. Its chemical composition was obtained by electron-probe microanalysis and the crystal-structure refinement; the empirical formula (V = 10 apfu) is (Na2.90K0.07Ca0.01Al0.01){sum}2.99{H2.98[V10O28]}{middle dot}15H2O, and the simplified formula is Na3{H3[V10O28]}{middle dot}15H2O. Rakovanite is monoclinic, space group P21/n, with a 12.0248(17), b 17.121(3), c 18.140(3) A, {beta} 106.242(8){degrees}, and Z = 4; the strongest four lines in the powder-diffraction pattern [d in A(I)(hkl)] are: 11.270(100)([IMG]f1.gif" ALT="Formula" BORDER="0"〉01), 7.696(81)(021), 8.709(78)(002), and 6.892(63)(120). The atomic arrangement of rakovanite has been refined to R1 = 0.0383; the structural unit in the phase is formed of a triply-protonated decavanadate polyanion, {H3[V10O28]}. The structural units are linked by the interstitial complexes, the (Na3{middle dot}15H2O) contents of which balance the +3 charges of the decavanadate polyanion with a NaO4(H2O)2 group, a Na2(H2O)10 dimer, and three H2O molecules that do not bond to the interstitial cations.

Description: Yttriaite-(Y), ideally Y2O3, is a new mineral (IMA2010-039) from the alluvial deposits of the Bol'shaya Pol'ya River, Subpolar Urals, Russia. The new mineral occurs as isolated crystals, typically cubo-octahedra

Description: Krotite, CaAl2O4, occurs as the dominant phase in an unusual Ca-,Al-rich refractory inclusion from the NWA 1934 CV3 carbonaceous chondrite. Krotite occupies the central and mantle portions of the inclusion along with minor perovskite, gehlenite, hercynite, and Cl-bearing mayenite, and trace hexamolybdenum. A layered rim surrounds the krotite-bearing regions, consisting from inside to outside of grossite, mixed hibonite, and spinel, then gehlenite with an outermost layer composed of Al-rich diopside. Krotite was identified by XRD, SEM-EBSD, micro-Raman, and electron microprobe. The mean chemical composition determined by electron microprobe analysis of krotite is (wt%) Al2O3 63.50, CaO 35.73, sum 99.23, with an empirical formula calculated on the basis of 4 O atoms of Ca1.02Al1.99O4. Single-crystal XRD reveals that krotite is monoclinic, P21/n; a = 8.6996(3), b = 8.0994(3), c = 15.217(1) A, {beta} = 90.188(6), and Z = 12. It has a stuffed tridymite structure, which was refined from single-crystal data to R1 = 0.0161 for 1014 Fo 〉 4{sigma}F reflections. Krotite is colorless and transparent with a vitreous luster and white streak. Mohs hardness is ~6[1/2]. The mineral is brittle, with a conchoidal fracture. The calculated density is 2.94 g/cm3. Krotite is biaxial (-), {alpha} = 1.608(2), {beta} = 1.629(2), {gamma} = 1.635(2) (white light), 2Vmeas = 54.4(5){degrees}, and 2Vcalc = 55.6{degrees}. No dispersion was observed. The optical orientation is X = b; Y {approx} a; Z {approx} c. Pleochroism is colorless to very pale gray, X 〉 Y = Z. Krotite is a low-pressure CaAl2O4 mineral, likely formed by condensation or crystallization from a melt in the solar nebula. This is the first reported occurrence of krotite in nature and it is one of the earliest minerals formed in the solar system.

Description: Postite, Mg(H2O)6Al2(OH)2(H2O)8(V10O28)·13H2O, is a new mineral species from the Vanadium Queen mine, La Sal Creek Canyon, and the Blue Cap mine, Lyon Canyon Creek, San Juan County, Utah, U.S.A. Postite occurs as very thin, needle-like prisms with pyramidal terminations; crystals commonly occur in parallel bundles and grow in divergent and “jackstraw” masses. Individual crystals are up to 1 mm long and 50 μm in diameter, and are golden-yellow with a yellow streak. The mineral is transparent, with a subadamantine luster; it does not fluoresce in short- or long-wave ultraviolet radiation. Postite has a Mohs hardness of approximately 2 and brittle tenacity. The mineral has one good cleavage on {001} and at least two perfect cleavages parallel to [001], possibly {100} and {010}. The fracture is splintery. The density calculated from the empirical formula using the single-crystal cell data is 2.226 g/cm3. Postite is biaxial (+) with a 2V angle of 71º. Indices of refraction for postite are α 1.727(3), β 1.733(3), and γ1.745(3). The optical orientation is X = c, Y = b, Z = a. Dispersion was not observed and pleochroism was not perceptible. Electron probe microanalysis and the crystal structure solution gave the empirical formula (Mg0.97Na0.06Ca0.04Sr0.01K0.01)∑1.09Al1.94 [(OH)1.92(H2O)0.08]‡”2.00 (V10O28)·27H2O. The simplified structural formula of postite is Mg(H2O)6Al2(OH)2(H2O)8(V10O28) ·13H2O. Postite is orthorhombic, Pccn, with a 16.3357(6), b 24.2434(17), c 11.7343(4) Å, V 4647.2(4) Å3, and Z = 4. The strongest four lines in the diffraction pattern are [d in Å(I)(hkl)]: 8.937(100)(111), 12.190(90)(020), 3.771(24)(113), and 8.248(22)(200). The atomic arrangement of postite was solved and refined to R1 = 0.0358. The structural unit is a decavanadate polyanion, [V10O28]6−; charge balance in the structure is maintained by the [Mg(H2O)6Al2(OH)2(H2O)8 ·13 H2O]6+ interstitial unit. The interstitial unit consists of a [Mg(H2O)6]2+ monomer, an [Al2(OH)2(H2O)8]4+ edge-sharing dimer, and thirteen additional H2O molecules. The linkage between the structural unit and the interstitial unit results from hydrogen bonding between oxygen atoms of the structural unit with hydrogen atoms of the [Al2(OH)2(H2O)8]4+ edge-sharing dimer and those of isolated H2O molecules. The new mineral is named in honor of Dr. Jeffrey E. Post (b. 1954), Curator-in-Charge of the National Gem and Mineral Collection, U. S. National Museum of Natural History (Smithsonian Institution).

Description: The new mineral reynoldsite, Pb2Mn4+2O5(CrO4), occurs at the Blue Bell claims, near Baker, San Bernardino County, California, U.S.A., and at the Red Lead mine, Dundas, Tasmania, Australia. At the Blue Bell claims, reynoldsite occurs in subparallel growths and divergent sprays of thin prisms with a square cross section. At the Red Lead mine, it occurs as thin rectangular blades. At both occurrences, crystals are small (≤0.2 mm), and ubiquitously and multiply twinned. At both deposits, reynoldsite formed as a secondary mineral derived from the weathering of primary minerals including oxides and sulfides in the presence of acidic groundwater. Reynoldsite is dark orange-brown to black in color and has a dark orange-brown streak. Its luster is subadamantine and its Mohs hardness is about 4½. The mineral is brittle with irregular to splintery fracture and a poorly developed {001} cleavage. The calculated density is 6.574 g/cm3 (Red Lead mine). The very high indices of refraction and dark color permitted only partial determination of the transmitted light optical properties. Electron microprobe analyses of Blue Bell and Red Lead reynoldsite provided the empirical formulas (based on nine O atoms): Pb1.97Mn2.01O5(Cr1.01O4) and (Pb2.07Sr0.04)∑2.11Mn2.15O5(Cr0.87O4), respectively. The strongest powder X-ray diffraction lines for Red Lead reynoldsite are [d(hkl)I]: 3.427(02̄1,110)52, 3.254(021,11̄2,12̄1)85, 3.052(1̄1̄2,111,02̄2,1̄03)100, 2.923(013,1̄22)40, 2.5015(004,2̄11,1̄30)47, 1.9818(01̄5,1̄05,202,23̄1)42, 1.7694(11̄5,13̄4,203,1̄42,1̄3̄3)36, and 1.6368(2̄2̄3,04̄3,221,124,22̄4)36. Reynoldsite is triclinic with space group P1̄ and unit-cell parameters: a = 5.0278(7), b = 7.5865(11), c = 10.2808(15) Å, α = 91.968(12), β = 99.405(12), γ = 109.159(10)°, V = 363.81(9) Å3, and Z = 2 (for a Red Lead mine crystal). The crystal structure of reynoldsite (R1 = 10.2% for 902 reflections with Fo 〉 4σF for a Red Lead crystal) contains close-packed layers of edge-sharing Mn4+O6 octahedra parallel to {001}. These layers are composed of edge-sharing double chains of octahedra extending along [100], which in turn are linked to one another by sharing edges in the [010] direction. The thick interlayer region contains Pb2+ cations and CrO4 tetrahedra. The 6s2 lone-electron pair of the Pb2+ is stereochemically active, resulting in a one-sided Pb-O coordination arrangement. The structure bears strong similarities to those of the phyllomanganates, such as chalcophanite and birnessite.