ALBERT

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.

Description: Castellaroite (IMA2015-071), Mn 2+ 3 (AsO 4 ) 2 ·4.5H 2 O, is a new secondary arsenate mineral from the Monte Nero mine, Rocchetta Vara, La Spezia, Liguria, Italy and the Valletta mine, near Canosio, Cuneo, Piedmont, Italy. It crystallized from As- and Mn-rich hydrothermal fluids in an oxidizing environment. At Monte Nero, it is associated with coralloite, manganohörnesite, rhodochrosite, sarkinite, sterlinghillite, strashimirite and wallkilldellite. At Valletta, it is associated with braccoite, hematite, manganberzeliite, orthoclase and tiragalloite. Castellaroite occurs as thin blades, flattened on [001], striated and elongated parallel to [100] and exhibiting the forms {110}, {012} and {001}. The mineral is colourless and transparent with a vitreous to silky lustre and white streak. Crystals are flexible with a curved fracture, and one perfect cleavage on {001}. The Mohs’ hardness is 21/2. The measured and calculated densities are 3.14(2) g·cm –3 and 3.164 g·cm –3 , respectively. The mineral is easily soluble in dilute HCl at room temperature. Optically, castellaroite crystals are biaxial (–), with α = 1.644(1), β = 1.662(1) and = 1.667(1) (white light); 2 V = 57(1)°; dispersion r 〈 v , moderate; the optical orientation Y = b ; Z a . The Raman spectrum is dominated by features corresponding to the AsO 4 group and also confirms the presence of H 2 O. Electron-microprobe analyses gave the empirical formula Mn 2+ 3.02 (As 1.94 P 0.06 ) 2.00 O 12.5 H 8.96 , based on 12.5 O apfu . Castellaroite is monoclinic, P 2 1 / n , with the unit-cell parameters: a = 8.7565(8), b = 13.4683(13), c = 18.652(2) Å, β = 94.876(7)°, V = 2191.7(4) Å 3 and Z = 8. The eight strongest lines in the X-ray powder diffraction pattern are [ d obs /Å ( I ) ( hkl )]: 10.90(100)(011), 9.27(67)(002), 6.97(42)( $$\overline{1}$$ 11), 3.323(47)(multiple), 3.043(87) ( $$\overline{1}$$ 134,204, $$\overline{2}$$ 232), 2.656(85)(multiple), 2.165(46)(multiple), and 1.5589(32)(multiple). The crystal structure was refined to R 1 = 0.118 for 2513 observed reflections [ F o 〉 4 F ]. The structure contains kinked chains of edge-sharing MnO 6 octahedra parallel to [100]. The chains are linked to each other by corner-sharing, forming sheets parallel to {001} and AsO 4 tetrahedra corner-link with octahedra in the sheet, forming a heteropolyhedral layer. Edge-sharing MnO 6 –MnO 5 dimers share corners with octahedra and tetrahedra in adjacent layers, thereby linking them in the [001] direction. The heteropolyhedral layer is topologically identical to those in the structures of the phosphate minerals: angarfite, bakhchisaraitsevite, mejillonesite, metaswitzerite, rimkorolgite and switzerite. Overall, the structure is most similar to that of metaswitzerite.

Description: Favreauite, ideally PbBiCu 6 O 4 (SeO 3 ) 4 · H 2 O, is a new secondary selenite mineral from the El Dragón mine, Antonio Quijarro Province, Potosí Department, Bolivia. The mineral occurs in vughs in a matrix of (Co, Cu)-rich penroseite, dolomite and goethite. Associated minerals are: ahlfeldite, allophane, calcite, chalcomenite, malachite, molybdomenite and an unnamed Al selenite. Favreauite forms tiny green square tabular crystals, flattened on {001}, up to 0.1 mm on edge and 0.01 mm thick, occurring in subparallel and divergent groups. The Mohs hardness of favreauite is estimated as 3; it has perfect cleavage on {001}, an irregular fracture and a vitreous lustre. The calculated density based on the empirical formula is 4.851 g cm –3 . Favreauite is uniaxial (–), with mean refractive index estimated as 1.854 from the Gladstone–Dale relationship. It is pleochroic in shades of green, O 〈 E . Electron microprobe analyses gave the empirical formula Pb 0.95 Ca 0.17 Bi 0.90 Cu 5.81 Se 4.10 O 16 (OH) · 1H 2 O, based on 18 O pfu . The Raman spectrum shows strong SeO 3 bands at 847 cm –1 ( 1 ), 764 and 795 cm –1 ( 3 ), 493 and 542 cm –1 ( 2 ), and 320 and 392 cm –1 ( 4 ). Favreauite is tetragonal, space group P 4/ n , with the unit-cell parameters: a = 9.860(4) Å, c = 9.700(5) Å, V = 943.0(9) Å 3 and Z = 2. The eight strongest lines in the X-ray powder diffraction pattern are [ d obs /Å ( I ) ( hkl )]: 5.67(100)(111), 3.470(76)(220,202), 3.190(35)(003), 2.961(40)(311,113), 2.709(33)(302,203), 2.632(34)(231,312), 2.247(36)(331,133), and 1.6652(33)(305,513,531). The crystal structure was refined to R 1 = 0.0329 for 1354 observed reflections [ F o 〉 4 F o ] and 0.0356 for all 1432 unique reflections. Favreauite is a close structural relative of nabokoite, KCu 7 Te 4+ O 4 (SO 4 ) 5 Cl, and atlasovite, KCu 6 Fe 3+ BiO 4 (SO 4 ) 5 Cl. In all cases, oxygen-centred tetrahedra share edges to form corrugated [Cu 6 M O 4 ] layers ( M = Bi or Te) which can be derived from the framework structure of murdochite, Pb 4+ Cu 2+ 6 O 8 - x (Cl,Br) 2 x by selective deletion of atoms. In favreauite, additional OH and H 2 O between the layers are weakly bound to Cu, giving it Jahn-Teller distorted 4 + 2 coordination. The Cu–Bi–O layer is braced by SeO 3 pyramids. The Bi 3+ and interlayer Pb 2+ form an approximately face-centred cubic array analogous to the Pb 4+ sites in murdochite. Unlike Bi 3+ , Pb 2+ is in a site with nonpolar $$\overline{4}$$ point symmetry, which suppresses the stereoactivity of its lone pair.

Description: Chiappinoite-(Y) (IMA2014-040), ideally Y 2 Mn(Si 3 O 7 ) 4 , is a new mineral found in peralkaline syenitic ejecta from the Água de Pau volcano, Sãn Miguel Island, Azores District, Portugal. It was discovered by collector Luigi Chiappino of Milan, Italy, after whom the mineral is named. It occurs as colourless, thin to thick prisms, up to 1 mm long, with blunt chisel-like terminations, and exhibits the forms {100}, {010}, {001}, {110} and {011}. Crystals are transparent with vitreous lustre. The Mohs hardness is about 6 and the mineral is brittle with uneven fracture and one perfect cleavage on {001}. The measured and calculated densities are 3.09(2) and 3.073 g/cm 3 , respectively. Chiappinoite-(Y) is biaxial (–) and the refractive indices (white light) are α = 1.590(1), β = 1.5978(10), = 1.5982(10); 2 V meas = 24(1)° and 2 V calc = 25°. The mineral exhibits no dispersion and is nonpleochroic. The optical orientation is X = c , Y = b , Z = a . The empirical formula on 28 O apfu is (Y 1.17 Ce 0.18 Dy 0.10 Na 0.10 Nd 0.09 Er 0.08 La 0.07 Gd 0.07 Yb 0.06 Sm 0.03 Pr 0.02 ) 1.97 (Mn 2+ 0.61 Ca 0.25 Fe 2+ 0.09 ) 0.95 Si 12.07 O 28 . The eight strongest reflections in the X-ray diffraction pattern [ d obs. in Å ( I ) ( hkl )] are: 9.84 (90) (002), 4.129 (52) (024), 3.977 (48) (114), 3.544 (100) (211,042,202), 3.203 (48) (222), 2.999 (71) (044,204), 2.478 (67) (310,046,206) and 2.065 (57) (multiple). The mineral is orthorhombic, Ibam , with a = 7.5549(3), b = 15.2342(5), c = 19.6418(14) Å, V = 2260.6(2) Å 3 and Z = 4. The structure of chiappinoite-(Y) contains 3-tetrahedra-thick silicate layers consisting of sinuous batisite-like chains, above and below which are four-membered silicate rings. Eight-coordinate Y and Mn sites are located between the silicate layers. The structure is essentially identical to that of the synthetic phases PrNaSi 6 O 14 and NdNaSi 6 O 14 , except that the latter phases have an additional 12-coordinate Na site within the "cage" in the silicate layer.

Description: New data for parnauite from the type locality, Majuba Hill, Nevada, USA (MH; type specimen), and also from Cap Garonne, Var, France (CG), and the Clara Mine, Baden-Württemberg, Germany, are presented. The average chemical composition of MH material is (Cu 8.82 Al 0.16 Fe 0.02 ) 9.00 (As 1.78 Al 0.07 Si 0.08 S 0.07 ) 2.00 O 8 (SO 4 )(OH) 10 ·7H 2 O and that of CG parnauite, (Cu 8.42 Al 0.21 Zn 0.10 ) 8.73 (AsO 4 ) 2 [(S 0.97 As 0.10 ) 1.07 O 4 ](OH 9.23 Cl 0.77 ) 10.00 · 7H 2 O. Both of these formulae confirm the 9:2:1 Cu:As:S ratio obtained from earlier descriptions of parnauite. Raman spectra for parnauite from both localities are very similar. Bands are assigned, but show no evidence of the presence of CO 3 , in contrast to previous studies, and no distinct Cu–Cl stretching mode. It appears that neither the minor CO 3 and PO 4 previously reported nor Cl are essential constituents of parnauite. Single-crystal XRD analysis indicates a primitive orthorhombic unit cell with dimensions 6 x 14 x 15 Å, similar to previous studies, but h = odd reflections were heavily streaked and diffuse, preventing full refinement. A 3 Å substructure was refined, with space group Pmn 2 1 , to R 1 ( F ) = 0.0750 (MH). For a MH crystal, the subcell had a = 3.0113(4), b = 14.259(3), c = 14.932(2) Å, V = 641.13(16) Å 3 and Z = 1. The structure is of a new type, and contains Cu in 6 distinct sites, forming two three-polyhedron wide ribbons of edge-sharing Cu-O polyhedra extended parallel to the a - axis. The two ribbons lie back-to-back and are bridged by two AsO 4 tetrahedra. The collection of 6Cu + 2As cations plus ligands forms a rod-like moiety extended || a . These rods link through polyhedral corners to form complex, corrugated (010) layers. The interlayer space is occupied by H 2 O molecules. Thus, the disorder observed by XRD is of an unusual type, in which the shape of the unit mesh within layers is variable, rather than the stacking of the layers. Disorder arises because each AsO 4 tetrahedron shares a face with a Cu(O,OH,H 2 O) 5–6 polyhedron in the substructure, necessitating partial occupancy of both As and Cu sites. The S atoms were not located in the refinement, but four electron-density maxima in the interlayer region were interpreted as H 2 O molecules. Hence, the simplified structural formula derived from the substructure is (Cu 10 2 )(As 2 2 )O 8 (OH) 14 ·8H 2 O, deviating from that obtained in chemical analyses. The discrepancy presumably arises due to strong delocalisation of the sulphur and the apical oxygen of the SO 4 tetrahedron in the substructure. Short-range order of Cu–As and Cu–S || a can occur independently in the relevant structural rods, which accounts for the observed long-range disorder. Cell parameters and substructures obtained from CG and Clara material are similar to those from the MH crystal. Site splitting of OH positions in the CG refinement indicates that Cl is distributed over several sites in the 3 Å substructure, making the mineral a Cl-rich variety of parnauite rather than a distinct mineral species.

Description: Peterandresenite (IMA2012-084), ideally Mn 4 Nb 6 O 19 ·14H 2 O, is the first naturally occurring hexaniobate. It was found at the AS Granit larvikite quarry in Tvedalen, Larvik, Vestfold, Norway, by private collector Peter Andresen, after whom the mineral is named. The mineral was found on fracture surfaces and in tiny vugs in the centre of a miaskitic pegmatite dike. It occurs as equidimensional, transparent to translucent orange crystals up to 1 mm with a pale orange streak and a vitreous to resinous lustre. The Mohs hardness is 2–2.5 and the mineral is brittle with uneven fracture and no cleavage. D (calc.) = 3.05 g/cm 3 and D (meas.) = 3.10(1) g/cm 3 . Peterandresenite is biaxial (–) and the refractive indices (white light) are: α = 1.760(5), β = 1.795(5) and = 1.800(5); 2V (meas.) = 43(2)° and 2V (calc.) = 40.7°. The mineral exhibits strong dispersion (r 〉 v) and is pleochroic with X (colourless) 〈 Z (pale orange) 〈〈 Y(medium orange). The optical orientation is: X c,y a*,Z = b. The empirical formula based on electron microprobe analyses is (Mn 3.92 Ca 0.05 Na 0.03 ) 4.00 (Nb 5.71 Mn 0 . 13 Fe 0 . 12 Si 0.03 ) 5.99 O 18.57 ·14H 2 O. The five strongest reflections in the X-ray diffraction pattern [ d obs. in Å ( I ) ( hkl )] are: 9.8977 (82) (001), 7.7104 (42) (110), 7.4689 (39) (20–1), 7.1026 (63) (11–1) and 2.9260 (100) (42–2). The mineral is monoclinic, C 2/ m , with a = 15.329(1), b = 9.4121(5), c = 11.2832(9) Å, β = 118.650(4)°, V = 1428.6(2) Å 3 and Z = 2. Peterandresenite has a novel structure consisting of six edge-sharing Nb-octahedra forming a super octahedron known as a Lindqvist ion. One Mn 2 + octahedron interconnects three Lindqvist ions to form a two-dimensional layer perpendicular to the c -axis. A second Mn 2+ octahedron bridging with the Lindqvist ion protrudes into the adjacent layer along the c -axis and creates a three-dimensional structure via hydrogen bonds.

Description: Alfredopetrovite, Al 2 (Se 4+ O 3 ) 3 · 6H 2 O, is a new secondary selenite mineral from the El Dragón mine, Antonio Quijarro Province, Potosí Department, Bolivia. The mineral occurs in vugs in a matrix of Co-rich krut’aite–penroseite, dolomite and goethite. Associated minerals are: ahlfeldite, allophane, calcite, chalcomenite, favreauite, felsőbányaite, malachite and molybdomenite. Crystals occur in drusy/scaly coatings and compact balls, the latter to 0.5 mm in diameter. Individual crystals are up to about 0.1 mm across. The Mohs hardness of alfredopetrovite is 21/2; it has no cleavage, curved fracture and a vitreous lustre. The calculated density based on the empirical formula is 2.504 g cm –3 . Alfredopetrovite is uniaxial (+), with = 1.554(2) and = 1.566(2) (white light), and exhibits no pleochroism. Electron microprobe analyses gave the empirical formula Al 1.94 Cu 0.07 Ni 0.03 Co 0.01 Se 2.95 O 15 H12.16, based on 15 O apfu . Alfredopetrovite is hexagonal, space group P $$\overline{6}$$ 2 c , with the unit-cell parameters: a = 8.818(3) Å, c = 10.721(2) Å, V = 722.0(5) Å 3 and Z = 2. The eight strongest lines in the X-ray powder diffraction pattern are [ d obs /Å ( I ) ( hkl )]: 7.63(55)(100), 6.22(55)(101), 5.37(26)(002), 4.398(40)(110,102), 3.404(100)(112), 2.783(50)(211), 2.606(22)(203), and 1.6609(26)(410,322,314,116). The crystal structure was refined to R 1 = 0.0268 for 240 observed reflections [ F o 〉 4 F ]. The structure is comprised of fairly regular AlO 6 octahedra and Se 4+ O 3 triangular pyramids. Three Se 4+ O 3 pyramids link two adjacent AlO 6 octahedra forming a [Al(H 2 O) 3 | 2 (Se 4+ O 3 ) 3 cluster structural unit. These structural units are bonded to one another only via hydrogen bonds yielding a structure with relatively large channels along [001]. The configuration of the cluster is similar to that of the distinctive unit in the NASICON structure, commonly referred to as a lantern unit .

Description: Wampenite, C 18 H 16 , is a new organic mineral from the fossil wood (conifer) locality at Wampen, Fichtelgebirge, Bavaria, Germany. It is monoclinic, space group P 2 1 / a , with a = 6.7331(19), b = 8.689(3), c = 23.709(7) Å, β = 90.118(6)°, V = 1387.0(7) Å 3 and Z = 4. Its structure was determined by single-crystal X-ray diffraction, which revealed that the molecular structure comprises an aromatic phenanthrene moiety with an axial methyl group at one end and a disordered propen-2-yl (methylvinyl) terminal group at the other. High resolution mass spectrometry (HRMS) confirmed the molecular formula C 18 H 16 and the IR spectrum is consistent with the molecular structure found.

Description: The new mineral plavnoite (IMA2015-059), ideally K 0.8 Mn 0.6 [(UO 2 ) 2 O 2 (SO 4 )]·3.5H 2 O, is a member of the zippeite group. It was found in the Plavno mine, in the eastern part of the Jáchymov ore district, Western Bohemia, Czech Republic, where it occurs as a supergene alteration phase formed by hydration–oxidation weathering of uraninite in hydrothermal U-veins. It was found to be associated with marécottite, magnesiozippeite, blatonite and gypsum. The mineral occurs as reddish to reddish-orange thin blades, elongated on [001] and flattened on {010}, which are intergrown in globular aggregates up to 0.5 mm across. Crystals are transparent with a vitreous to silky lustre. The streak is pale orange. The mineral is non-fluorescent under both long- and short-wave ultraviolet (UV) radiation. The Mohs hardness is about 2. Crystals are brittle with perfect {010} cleavage and uneven fracture. The density calculated from the empirical formula is 4.926 g cm –3 . Optically, plavnoite is biaxial (+), with α = 1.740(5), β = 1.770(5), = 1.850 (5) (measured in white light). The measured 2 V is 64.6(4)°; the calculated 2 V is 65.3°. Dispersion could not be observed; no pleochroism was observed. Electron-microprobe analyses yielded the empirical formula (based on 2U atoms per formula unit, apfu) K 0.77 (Mn 0.51 Zn 0.04 Ni 0.03 Mg 0.02 ) 0.60 [(UO 2 ) 2 O 1.08 (OH) 0.92 (SO 4 ) 0.96 (SiO 4 ) 0.24 ](H 2 O) 3.50 . Plavnoite is monoclinic, C 2/ c , a = 8.6254 (16), b = 14.258(3), c = 17.703(4) Å, β = 104.052(18)°, V = 2122.0(8) Å 3 and Z = 8. The structure ( R 1 = 4.99 % for 989 reflections with I 〉 3[ I ]) contains UO 7 pentagonal bipyramids and SO 4 tetrahedra forming sheets of the well-known zippeite topology. The interlayer region contains infinite zig–zag chains of corner-sharing Mn 2+ 6 octahedra ( = O, H 2 O) with K-centred polyhedra. The K atom sits at the partially occupied, mixed K/O site, the non-shared corner of the Mn2 octahedron. The mineral is named after the type locality – the Plavno mine.