ALBERT

Description: The new pyroxenoid barrydawsonite-(Y) occurs at the Merlot Claim, North Red Wine Pluton, Labrador, Canada (62°32'38.54'' W; 54°08'1.37'' N). The host rock is a metamorphosed eudialyte syenite consisting of eudialyte, potassic arfvedsonite, jadeitic aegirine, nepheline, albite and potassium feldspar with accessory Y-bearing pectolite, britholite and steenstrupine. Barrydawsonite-(Y) crystals commonly have discrete thin rims of Y-bearing pectolite. The average empirical formula (based on nine anions p.f.u.) is Na 1.54 Ca 0.74 Mn 0.15 Fe 0.07 Y 0.38 Nd 0.01 Sm 0.01 Gd 0.02 Tb 0.01 Dy 0.04 Ho 0.01 Er 0.02 Yb 0.01 Si 3.00 O 9 H. The simplified formula is Na 1.5 Y 0.5 CaSi 3 O 9 H. Barrydawsonite-(Y) is related to pectolite by the substitution 1/2[Na M 3+ Ca –2 ] ( M 3+ = Y, REE ), and is exceptional in being the only member of the pectolite group that has the structure of the monoclinic M2abc polytype. The crystal structure has been determined in monoclinic space group P 2 1 / a : a = 15.5026(2), b = 7.0233(1), c = 6.9769(1) Å, β = 95.149(1)°, V = 756.58(2) Å 3 ( Z = 4). Final agreement indices are R 1 = 0.038, wR 2 = 0.068, Goof = 1.136. The asymmetric unit of barrydawsonite-(Y) has three metal sites: M (1) = Ca, M (2) = Na 0.5 (Y, REE ) 0.5 , M (3) = Na. M (1) and M (2) are octahedrally-coordinated sites, whereas M (3) is [8]-coordinated as in pectolite and serandite. The structural formula for the empirical composition is M (3) Na 1.00 M (2) (Na 0.50 Y 0.38 REE 0.13 ) =1.01 M (1) (Na 0.04 Ca 0.74 $${\mathrm{Mn}}_{0.15}^{2+}$$ $${\mathrm{Fe}}_{0.07}^{2+}$$ ) =1.00 Si 3 O 9 H. There is excellent agreement between the refined site-scattering values and those calculated based upon the structural formula. Barrydawsonite-(Y) is biaxial (+) with α = 1.612(1), β = 1.617(1), = 1.630(1) (white light) and 2V = 63(1)°. The five strongest peaks in the X-ray powder diffraction pattern are [ d obs ( Å), I obs %, ( hkl )]: [2.905, 100, (023)], [3.094, 30, (210,2I11,1I21,202)], [1.7613, 29, (127,323,040)], [3.272, 27, (2I02,104)], [1.7016, 27, (140,2I27,3I25)].

Description: The new minerals bobcookite (IMA 2014-030), NaAl(UO 2 ) 2 (SO 4 ) 4 ·18H 2 O and wetherillite (IMA 2014-044), Na 2 Mg(UO 2 ) 2 (SO 4 ) 4 ·18H 2 O, were found in the Blue Lizard mine, San Juan County, Utah, USA, where they occur together as secondary alteration phases in association with boyleite, chalcanthite, dietrichite, gypsum, hexahydrite, johannite, pickeringite and rozenite. Bobcookite descriptive details: lime green to greenish-yellow massive veins and columnar crystals; transparent; vitreous lustre; bright greenish-white fluorescence; pale greenish yellow streak; hardness (Mohs) 21/2; brittle; conchoidal fracture; no cleavage; moderately hygroscopic; easily soluble in cold H 2 O; density calc = 2.669 g cm –3 . Optically, biaxial (–), α = 1.501(1), β = 1.523(1), = 1.536(1) (white light); 2V meas. = 78(1)°; 2V calc. = 74°; dispersion r 〈 v , moderate. Pleochroism: X colourless, Y very pale yellow-green, Z pale yellow-green; X 〈 Y 〈 Z . EDS analyses yielded the empirical formula Na 0.97 Al 1.09 (U 1.02 O 2 ) 2 (S 0.98 O 4 ) 4 (H 2 O) 18 . Bobcookite is triclinic, P 1I, a = 7.7912(2), b = 10.5491(3), c = 11.2451(8) Å, α = 68.961(5), β = 70.909(5), = 87.139(6)°, V = 812.79(8) Å 3 and Z = 1. The structure ( R 1 = 1.65% for 3580 F o 〉 4 F ) contains [(UO 2 )(SO 4 ) 2 (H 2 O)] chains linked by NaO 4 (H 2 O) 2 octahedra to form layers. Hydrogen bonds to insular Al(H 2 O) 6 octahedra and isolated H 2 O groups hold the structure together. The mineral is named for Dr Robert (Bob) B. Cook of Auburn University, Alabama, USA. Wetherillite descriptive details: pale greenish-yellow blades; transparent; vitreous lustre; white streak; hardness (Mohs) 2; brittle; two cleavages, {101I} perfect and {010} fair; conchoidal or curved fracture; easily soluble in cold H 2 O; density calc = 2.626 g cm –3 . Optically, biaxial (+), α = 1.498(1), β = 1.508(1), = 1.519(1) (white light); 2V meas. = 88(1)°, 2V calc. = 87.9°; dispersion is r 〈 v , distinct; optical orientation: Z = b, X ^ a = 54° in obtuse β; pleochroism: X colourless, Y pale yellow-green, Z pale yellow-green; X 〈 Y Z . EDS analyses yielded the empirical formula Na 1.98 (Mg 0.58 Zn 0.24 Cu 0.11 $${\mathrm{Fe}}_{0.09}^{2+}$$ ) 1.02 (U 1.04 O 2 ) 2 (S 0.98 O 4 ) 4 (H 2 O) 18 . Wetherillite is monoclinic, P 2 1 / c, a = 20.367(1), b = 6.8329(1), c = 12.903(3) Å, β = 107.879(10)°, V = 1709.0(5) Å 3 and Z = 2. The structure ( R 1 = 1.39% for 3625 F o 〉 4 F ) contains [(UO 2 )(SO 4 ) 2 (H 2 O)] sheets parallel to {100}. Edge-sharing chains of Na(H 2 O) 5 O polyhedra link adjacent uranyl sulfate sheets forming a weakly bonded three-layer sandwich. The sandwich layers are linked to one another by hydrogen bonds through insular Mg(H 2 O) 6 octahedra and isolated H 2 O groups. The mineral is named for John Wetherill (1866–1944) and George W. Wetherill (1925–2006).

Description: Apexite (IMA2015-002), NaMg(PO 4 )·9H 2 O, is a new mineral from the Apex mine, Lander County, Nevada, U.S.A., where it occurs as a low-temperature secondary mineral on massive quartz matrix in association with andersonite, calcite, čejkaite, gaylussite, and goethite. Apexite forms colorless needles up to 0.5 mm in length. The streak is white. Crystals are transparent and have vitreous to satiny luster. The Mohs hardness is about 2, the tenacity is brittle, the fracture is curved, and crystals exhibit one perfect cleavage on {100}. The measured density is 1.74(1) g/cm 3 and the calculated density is 1.741 g/cm 3 . Electron microprobe analyses provided: Na 2 O 9.26, MgO 14.42, P 2 O 5 23.31, H 2 O 53.01 (structure), total 100.00 wt% (normalized). The empirical formula (based on 13 O apfu) is: Na 0.91 Mg 1.09 P 1.00 O 13.00 H 17.91 . Apexite is triclinic, P , a = 6.9296(7), b = 11.9767(13), c = 14.9436(19) Å, α = 92.109(6), β = 102.884(7), = 105.171(7)°, V = 1160.9(2) Å 3 , and Z = 4. The eight strongest lines in the X-ray powder diffraction pattern are [ d obs in Å( I )( hkl )]: 14.63(35)(001); 5.11(61)(021, 1,110,20); 4.68(75)(02, 2,11,03); 4.301(96)(102,013,022,13); 4.008(44)( 3,12); 2.876(46)(040); 2.762(100)( 3,21,04,04,015); and 2.507(30)(212,025, 3). Apexite is a new struvite-type phase with a unique structure ( R 1 = 4.44% for 1401 F o 〉 4 F ) consisting of four components: (1) a [Na 2 Mg 4 (H 2 O) 14 ] 10+ heteropolyhedral cation cluster; (2) a trans edge-sharing chain of Na(H 2 O) 6 octahedra; (3) an isolated PO 4 group; and (4) an isolated H 2 O group. The structural components are linked to one another only via hydrogen bonds. Its structure is related to that of hazenite.

Description: Nizamoffite, ideally Mn 2+ Zn 2 (PO 4 ) 2 (H 2 O) 4 , is a new mineral from the Palermo No.1 pegmatite in North Groton, Grafton County, New Hampshire, U.S.A. It formed as the result of secondary alteration of primary triphylite and associated sphalerite. The crystals occur as colorless prisms up to 1 mm in length and 0.5 mm in diameter. The prisms are elongated and lightly striated parallel to [001] and exhibit the forms {100}, {010}, {230}, {011}, {031}, and {111}. The mineral is transparent and has a white streak, vitreous luster, Mohs hardness of about 31/2, brittle tenacity, irregular fracture, and three cleavages: perfect on {010}, good on {100}, and fair on {001}. The measured and calculated densities are 3.00(1) and 2.961 g/cm 3 , respectively. It is optically biaxial (–), α = 1.580(1), β = 1.590(1), = 1.591(1) (white light), 2 V meas = 28(1)°, and 2 V calc = 35°. Nizamoffite exhibits strong dispersion, r 〈 v . The optical orientation is X = a , Y = c , Z = b , and the mineral is nonpleochroic. Electron-microprobe analyses (average of 10), with H 2 O calculated on structural grounds, provided: CaO 0.20, MgO 0.61, MnO 15.80, ZnO 33.34, Fe 2 O 3 2.81, Al 2 O 3 0.10, P 2 O 5 32.05, H 2 O 15.95, total 100.23 wt%. The empirical formula (based on 12 O atoms) is: (Mn 2+ 0.99 Ca 0.02 ) 1.01 (Zn 1.82 Fe 3+ 0.12 Mg 0.07 ) 2.01 (P 1.00 O 4 ) 2 (H 1.96 O) 4 . The mineral dissolves readily in cold, dilute HCl. Nizamoffite is orthorhombic, Pnma , with the unit-cell parameters: a = 10.6530(4), b = 18.4781(13), c = 5.05845(15) Å, V = 995.74(8) Å 3 , and Z = 4. The eight strongest lines in the X-ray powder diffraction pattern are [ d obs in Å( I )( hkl )]: 9.27(71)(020); 4.62(37)(040,220); 4.43(24)(111); 3.424(52)(240,221); 2.873(100)(241); 2.644(36)(400,331); 2.540(33)(420,161,002); and 1.953(36)(281). Nizamoffite is isostructural with hopeite. The structure ( R 1 = 1.7% for 1014 F o 〉 4 F ) contains corner-sharing zigzag chains of ZnO 4 tetrahedra along [001]. The chains are connected by corner sharing with PO 4 tetrahedra to form sheets parallel to {010}. Three of the four PO 4 vertices link to ZnO 4 tetrahedra in the sheet, while the fourth links to an octahedron between the sheets. Each octahedron links to one tetrahedron from each of two adjacent sheets, thereby linking the sheets in the [010] direction. The octahedron contains Zn in hopeite and Mn in nizamoffite.

Description: Tapiaite (IMA2014-024), Ca 5 Al 2 (AsO 4 ) 4 (OH) 4 ·12H 2 O, is a new mineral from the Jote mine, Tierra Amarilla, Copiapó Province, Atacama, Chile. The mineral is a late-stage, low-temperature, secondary mineral occurring with conichalcite, joteite, mansfieldite, pharmacoalumite, pharmacosiderite and scorodite in narrow seams and vughs in the oxidized upper portion of a hydrothermal sulfide vein hosted by volcanoclastic rocks. Crystals occur as colourless blades, flattened on {101I} and elongated and striated along [010], up to ~0.5 mm long, and exhibiting the forms {101I}, {101} and {111}. The blades are commonly intergrown in subparallel bundles and less commonly in sprays. The mineral is transparent and has a white streak and vitreous lustre. The Mohs hardness is estimated to be between 2 and 3, the tenacity is brittle, and the fracture is splintery. It has two perfect cleavages on {101} and {101I}. The calculated density based on the empirical formula is 2.681 g cm –3 . It is optically biaxial (+) with α = 1.579(1), β = 1.588(1), = 1.610(1) (white light), 2V meas = 66(2)° and 2V calc = 66°. The mineral exhibits no dispersion. The optical orientation is X [101I]; Y = b, Z [101]. The electron-microprobe analyses (average of five) provided: Na 2 O 0.09, CaO 24.96, CuO 0.73, Al 2 O 3 10.08, Fe 2 O 3 0.19, As 2 O 5 40.98, Sb 2 O 5 0.09, H 2 O 23.46 (structure), total 100.58 wt.%. In terms of the structure, the empirical formula (based on 32 O a.p.f.u.) is (Ca 4.83 $${\mathrm{Cu}}_{0.10}^{2+}$$ Na 0.03 ) 4.96 (Al 2.14 $${\mathrm{Fe}}_{0.03}^{3+}$$ ) 2.17 [( $${\mathrm{As}}_{3.87}^{5+}$$ $${\mathrm{Sb}}_{0.01}^{5+}$$ ) 3.88 O 16 ][(OH) 3.76 (H 2 O) 0.24 ] 4 (H 2 O) 10 ·2H 2 O. The mineral is easily soluble in RT dilute HCl. Tapiaite is monoclinic, P 2 1 / n , with unit-cell parameters a = 16.016(1), b = 5.7781(3), c = 16.341(1) Å, β = 116.704(8)°, V = 1350.9(2) Å 3 and Z = 2. The eight strongest lines in the powder X-ray diffraction pattern are [ d obs Å ( I )( hkl )]: 13.91(100)(1I01), 7.23(17)(200,002), 5.39(22)(110,011), 4.64(33)(1I12,2I11,3I03), 3.952(42)(1I13,3I11,2I13), 3.290(35)(2I14,4I12,1I14,4I11), 2.823(39)(303,3I15) and 2.753(15)(5I13,1I15,121,5I11). The structure of tapiaite ( R 1 = 5.37% for 1733 F o 〉 4 F ) contains Al(AsO 4 )(OH) 2 chains of octahedra and tetrahedra that are topologically identical to the chain in the structure of linarite. CaO 8 polyhedra condense to the chains, forming columns, which are decorated with additional peripheral AsO 4 tetrahedra. The CaO 8 polyhedra in adjacent columns link to one another by corner-sharing to form thick layers parallel to {101I} and the peripheral AsO 4 tetrahedra link to CaO 6 octahedra in the interlayer region, resulting in a framework structure.

Description: The system B 2 O 3 -Al 2 O 3 -SiO 2 (BAS) includes two ternary phases occurring naturally, boromullite, Al 9 BSi 2 O 19 , and boralsilite, Al 16 B 6 Si 2 O 37 , as well as synthetic compounds structurally related to mullite. The new mineral vránaite, a third naturally occurring anhydrous ternary BAS phase, is found with albite and K-feldspar as a breakdown product of spodumene in the elbaite-subtype Manjaka granitic pegmatite, Sahatany Valley, Madagascar. Boralsilite also occurs in this association, although separately from vránaite; both minerals form rare aggregates of subparallel prisms up to 100 μm long. Optically, vránaite is biaxial (–), n α = 1.607(1), n β = 1.634(1), n = 1.637(1) (white light), 2 V x (calc) = 36.4°, X c ; Y a ; Z = b . An averaged analysis by EMP and LA-ICP-MS (Li, Be) gives (wt%) SiO 2 20.24, B 2 O 3 11.73, Al 2 O 3 64.77, BeO 1.03, MnO 0.01, FeO 0.13, Li 2 O 1.40, Sum 99.31. Raman spectroscopy in the 3000–4000 cm –1 region rules out the presence of significant OH or H 2 O. Vránaite is monoclinic, space group I 2/ m , a = 10.3832(12), b = 5.6682(7), c = 10.8228(12) Å, β = 90.106(11)°; V = 636.97(13) Å 3 , Z = 1. In the structure [ R 1 = 0.0416 for 550 F o 〉 4 F o ], chains of AlO 6 octahedra run parallel to [010] and are cross-linked by Si 2 O 7 disilicate groups, BO 3 triangles, and clusters of AlO 4 and two AlO 5 polyhedra. Two Al positions with fivefold coordination, Al4 and Al5, are too close to one another to be occupied simultaneously; their refined site-occupancy factors are 54% and 20% occupancy, respectively. Al5 is fivefold-coordinated Al when the Al9 site and both O9 sites are occupied, a situation giving a reasonable structure model as it explains why occupancies of the Al5 and O9 sites are almost equal. Bond valence calculations for the Al4 site suggest Li is likely to be sited here, whereas Be is most probably at the Al5 site. One of the nine O sites is only 20% occupied; this O9 site completes the coordination of the Al5 site and is located at the fourth corner of what could be a partially occupied BO 4 tetrahedron, in which case the B site is shifted out of the plane of the BO 3 triangle. However, this shift remains an inference as we have no evidence for a split position of the B atom. If all sites were filled (Al4 and Al5 to 50%), the formula becomes Al 16 B 4 Si 4 O 38 , close to Li 1.08 Be 0.47 Fe 0.02 Al 14.65 B 3.89 Si 3.88 O36.62 calculated from the analyses assuming cations sum to 24. The compatibility index based on the Gladstone-Dale relationship is 0.001 ("superior"). Assemblages with vránaite and boralsilite are inferred to represent initial reaction products of a residual liquid rich in Li, Be, Na, K, and B during a pressure and chemical quench, but at low H 2 O activities due to early melt contamination by carbonate in the host rocks. The two BAS phases are interpreted to have crystallized metastably in lieu of dumortierite in accordance with Ostwald Step Rule, possibly first as "boron mullite," then as monoclinic phases. The presence of such metastable phases is suggestive that pegmatites crystallize, at least partially, by disequilibrium processes, with significant undercooling, and at high viscosities, which limit diffusion rates.

Description: Ferraioloite, MgMn 2+ 4 (Fe 2+ 0.5 Al 3+ 0.5 ) 4 Zn 4 (PO 4 ) 8 (OH) 4 (H 2 O) 20 , is a new secondary phosphate mineral from the Foote Lithium Company mine, Kings Mountain district, Cleveland County, North Carolina, USA. The mineral was found in tiny vughs within a thin seam of very fine-grained, sugary pegmatite with vivianite, fairfieldite/messelite, phosphophyllite, scholzite/parascholzite, rittmannite, mangangordonite, kingsmountite, kastningite and metaswitzerite. Ferraioloite crystals occur as very thin greenish grey to lemon yellow plates or blades up to about 0.2 mm in length, but no more than a few μm thick. Crystals are biaxial (–), with indices of refraction α = 1.575(calc), β = 1.5825(5), = 1.5835(5), 2 V (meas.) = 40(5)°. Dispersion is weak: r 〉 v , the orientation is: X a , Y = b , Z c and pleochroism: X , Z = colourless, Y = blue grey; Y 〉 〉. X Z . The empirical formula (based on 56 O atoms pfu) is Ca 0.21 Mg 0.50 Mn 2+ 4.16 Fe 2+ 2.05 Al 3+ 2.01 Zn 4.27 P 8.00 H 43.59 O 56 . Ferraioloite is monoclinic, space group I 2/ m , with the unit-cell parameters: a = 25.333(3) Å, b = 6.299(1) Å, c = 15.161(3) Å, β = 90.93(3)° and V = 2419.0(2) Å 3 . Ferraioloite has a heteropolyhedral layer structure with layers parallel to (100) and with isolated Mg(H 2 O) 6 octahedra and water molecules packing between the layers. The heteropolyhedral slabs have the same topology as falsterite, with Mn 2+ replacing Ca 2+ and with Al 3+ substituting for Fe 3+ .

Description: Kayrobertsonite, MnAl 2 (PO 4 ) 2 (OH) 2 ·6H 2 O, is a new secondary phosphate mineral from the Hagendorf Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany and the Foote Lithium Company mine, Kings Mountain district, Cleveland County, North Carolina, USA. Kayrobertsonite crystals occur as intergrown masses of snow-white, soft, finely fibrous needles, less than 5 μm in diameter and no more than 100 μm in length. Quantitative analysis of Foote mine kayrobertsonite gave the empirical formula: Mn 0.97 Ca 0.03 Fe 0.02 Al 1.87 (PO 4 ) 2 (OH) 1.62 F 0.03 (H 2 O) 0.38 ·6H 2 O; and for Hagendorf Süd kayrobertsonite: Mn 0.92 Ca 0.06 Fe 0.02 Al 1.87 (PO 4 ) 2 (OH) 1.19 F 0.42 (H 2 O) 0.39 ·6H 2 O. Foote mine kayrobertsonite crystals are biaxial (–), with indices of refraction α = 1.530(1), β = 1.554(1), = 1.566(1), measured in white light; 2 V (meas.) is 70.3(5)°, while 2 V (calc.) is 69.6°. The mineral is nonpleochroic. The orientation of the crystals is Z c (length slow). Kayrobertsonite is triclinic, space group $$P\overline{1}$$ , with the unit-cell parameters: a = 10.049(2), b = 10.205(2), c = 6.083(1) Å, α = 91.79(3), β = 99.70(3), = 98.02(3)°, V = 607.9(2) Å 3 and Z = 2 (Foote mine). The polyhedral framework in kayrobertsonite has the same topology as that in nordgauite, but with replacement of F by OH at the bridging anion sites. The main crystal chemical change from nordgauite to kayrobertsonite is a doubling of the number of water molecules in the [001] channels.