Günter Blass

Lileyite, Ba2(Na,Fe,Ca)3MgTi2(Si2O7)2O2F2, a new lamprophyllite-group mineral from the Eifel volcanic area, Germany

The new Mg- and F-dominant lamprophyllite-group mineral lileyite (IMA 2011-021) was found at the Lohley quarry, Udersdorf, near Daun, Eifel Mountains, Rhineland-Palatinate (Rheinland-Pfalz), Germany, and named for the old name of the type locality, Liley. Associated minerals are nepheline, leucite, augite, magnetite, fluorapatite, perovskite, gotzenite. Lileyite is brown, translucent; streak is white. It forms platy crystals up to 0.1 × 0.3 × 0.5 mm in size and their clusters up to 1 mm across on the walls of cavities in an alkaline basalt. Lileyite is brittle, with Mohs hardness of 3–4 and perfect cleavage on (001). D calc is 3.776 g/cm 3 . The new mineral is biaxial (+), α = 1.718(5), β = 1.735(5), γ = 1.755(5), 2V (meas.) = 75(15)°, 2V (calc.) = 86°. The IR spectrum is given. The chemical composition is (EDS-mode electron microprobe, mean of 5 analyses, wt%): SiO 2 28.05, BaO 26.39, TiO 2 18.53, Na 2 O 6.75, MgO 4.58, FeO 4.48, CaO 2.30, SrO 2.23, MnO 1.44, K 2 O 1.41, Nb 2 O 5 0.95, F 3.88, –O=F 2 -1.63; total 99.36. The empirical formula based on 18 anions is: Ba 1.50 Sr 0.19 K 0.26 Na 1.89 Ca 0.36 Mn 0.18 Mg 0.99 Fe 0.54 Ti 2.01 Nb 0.06 Si 4.06 O 16.23 F 1.77 . The simplified formula is: Ba 2 (Na,Fe,Ca) 3 MgTi 2 (Si 2 O 7 ) 2 O 2 F 2 . The crystal structure was solved using single-crystal X-ray diffraction data ( R = 0.024). Lileyite is monoclinic, space group C 2/ m , a = 19.905(1), b = 7.098(1), c = 5.405(1) A, β = 96.349(5)°, V = 758.93(6) A 3 , Z = 2. The strongest lines of the powder diffraction pattern [ d , A ( I , %) ( hkl )] are: 3.749 (45) (31–1), 3.464 (76) (510, 311, 401), 3.045 (37) (51–1), 2.792 (100) (221, 511), 2.672 (54) (002, 601, 20-2), 2.624 (43) (710, 42–1). Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, registration number 4106/1.

Ferriallanite-(La), a new member of the epidote supergroup from the Eifel, Germany

The new mineral ferriallanite-(La) (IMA 2010-066), ideally CaLaFe 3+ AlFe 2+ (SiO 4 )(Si 2 O 7 )O(OH), is a member of the epidote supergroup and the La analogue of ferriallanite-(Ce). It occurs as a single, thick, tabular {100} crystal (2 mm in its longest dimension) in a void of a sanidinite xenolith found in the In den Dellen pumice quarries, Niedermendig, Mendig, Laach Lake volcanic complex, Eifel Mountains, Rhineland-Palatinate, Germany. Ferriallanite-(La) is associated with sanidine, minor “biotite”, magnetite, nosean (grey, rounded grains) and trace amounts of dark green clinopyroxene. It is black, translucent in very thin splinters, with a brown streak, vitreous lustre, no cleavage, irregular to conchoidal fracture, Mohs hardness of ca . 6, D calc. = 4.208 g cm −3 (for empirical formula) and D x = 4.099 g cm −3 . Optically, it is biaxial negative, with α = 1.791(5), β = 1.827(6), γ = 1.845(5) (white light), 2 V α (calc.) = 69°. The mineral is non-fluorescent and shows strong pleochroism, X = pale brownish, Y = greyish brown, Z = dark red-brown; absorption Z > Y >> X, orientation unknown. Dispersion is weak and the sign could not be determined. Electron microprobe analysis yielded the empirical formula (based on 12 O atoms and 1 OH group pfu): Ca 0.98 (La 0.47 Ce 0.41 Th 0.08 Nd 0.02 Pr 0.02 ) ∑1.00 (Fe 3+ 0.81 Al 0.14 ) ∑0.95 Al 1.00 (Fe 2+ 0.47 Mn 0.28 Ti 0.16 Mg 0.05 ) ∑0.96 [(Si 0.93 Al 0.05 ) ∑0.98 O 4 ](Si 2 O 7 )O(OH). Ferriallanite-(La) is monoclinic, space group P 2 1 / m , with a = 8.938(2), b = 5.789(1), c = 10.153(2) A, β = 114.54(3)°, V = 477.88(6) A 3 (single-crystal data) and Z = 2. Strongest eight lines in the X-ray powder diffraction pattern are [ d in A( I ) hkl ]: 9.22 (19) 001; 7.96 (34) 101; 3.53 (38) 211; 2.92 (100) 302, 113; 2.72 (50) 120, 013; 2.63 (36) 311; 2.16 (17) 221 and 1.639 (34) 106, 424. A single-crystal X-ray structure refinement [ R 1( F ) = 0.0150] and a derivation of the M 3 site population from the chemical-analytical data yielded the formula A 1 Ca 1.00 A 2 (La 0.49 Ce 0.42 Ca 0.09 ) M 1 (Fe 0.58 Al 0.42 ) M 2 (Al 0.94 Fe 0.06 ) M 3 (Fe 0.49 Mn 0.29 Ti 0.17 Mg 0.05 ) ∑1.00 (SiO 4 )(Si 2 O 7 )O(OH), in reasonably good agreement with the electron microprobe data. The site refinements clearly show that there is some minor Fe at the M 2 site, in contrast to the formula calculated using currently recommended methods for members of the epidote supergroup.

Hillesheimite, (K,Ca,□)2(Mg,Fe,Ca,□)2[(Si,Al)13O23(OH)6](OH) · 8H2O, a new phyllosilicate mineral of the Günterblassite group

A new mineral, hillesheimite, has been found in the Graulai basaltic quarry, near the town of Hillesheim, the Eifel Mountains, Rhineland-Palatinate (Rheinland-Pfalz), Germany. It occurs in the late assemblage comprising nepheline, augite, fluorapatite, magnetite, perovskite, priderite, götzenite, lamprophyllite-group minerals, and åkermanite. Colorless flattened crystals of hillesheimite reaching 0.2 × 1 × 1.5 mm in size and aggregates of the crystals occur in miarolitic cavities in alkali basalt. The mineral is brittle, with Mohs’ hard-ness 4. Cleavage is perfect parallel to (010) and distinct on (100) and (001). Dcalc = 2.174 g/cm3, Dmeas = 2.16(1) g/cm3. IR spectrum is given. Hillesheimite is biaxial (−), α = 1.496(2), β = 1.498(2), γ = 1.499(2), 2Vmeas = 80°. The chemical composition (electron microprobe, mean of 4 point analyses, H2O determined from structural data, wt %) is as follows: 0.24 Na2O, 4.15 K2O, 2.14 MgO, 2.90 CaO, 2.20 BaO, 2.41 FeO, 15.54 Al2O3, 52.94 SiO2, 19.14 H2O, total is 101.65. The empirical formula is: K0.96Na0.08Ba0.16Ca0.56Mg0.58Fe0.372+[Si9.62Al3.32O23(OH)6][(OH)0.82(H2O)0.18] · 8H2O. The crystal structure has been determined from X-ray single-crystal diffraction data, R = 0.1735. Hillesheimite is orthorhombic, space group Pmmn, the unit-cell dimensions are: a = 6.979(11), b = 37.1815(18), c = 6.5296(15) Å; V=1694(3) Å3, Z = 2. The crystal structure is based on the block [(Si,Al)13O25(OH)4] consisting of three single tetrahedral layers linked via common vertices and is topologically identical to the triple layers in günterblassite and umbrianite. The strong reflections [d Å (I %)] in the X-ray powder diffraction pattern are: 6.857(58), 6.545(100), 6.284(53), 4.787(96), 4.499(59), 3.065(86), 2.958(62), 2.767(62). The mineral was named after its type locality. Type specimens are deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, registration number 4174/1.

Windhoekite, Ca2Fe3+3−x(Si8O20)(OH)4·10H2O, a new palygorskite-group mineral from the Aris phonolite, Namibia

The new mineral windhoekite was discovered in a specimen from the Ariskop Quarry, near Windhoek, Namibia. Associated minerals are fluorapophyllite, aegirine, microcline, arisite-(Ce), arisite-(La). Windhoekite is yellow-brown, translucent; streak is beige. It forms isolated long-prismatic crystals up to 0.15 × 4 mm and their radial aggregates in cavities in phonolite. D calc is 2.630 g/cm 3 , D meas is 2.62 (2) g/cm 3 . The new mineral is biaxial (−), α = 1.610(3), β = 1.662(3), γ = 1.671(3), 2V (meas.) = 50(10)°, 2V (calc.) = 44°. Dispersion is not observed, pleochroism is strong ( Y ≈ Z > X, brown to dark brown), orientation: X ≈ a; Z = c . The IR spectrum is given. The chemical composition is (electron microprobe, mean of 5 analyses, wt%): CaO 9.24, MnO 0.85, Fe 2 O 3 23.14, Al 2 O 3 0.41, SiO 2 46.32, H 2 O (by gas chromatography) 21.0; total 100.96. The empirical formula based on 34 O atoms is: (Ca 1.68 Mn 0.12 )Fe 3+ 2.96 (Si 7.87 Al 0.08 O 20 )(OH) 4 ·10H 1.98 O. The simplified formula is: Ca 2 Fe 3+ 3− x [(Si,Al) 8 O 20 ](OH) 4 ·10H 2 O. The crystal structure was solved using single-crystal diffraction data. Windhoekite is monoclinic, space group C 2/ m , a = 14.319(5), b = 17.825(4), c = 5.242(1) A, β = 103.5(2)°, V = 1301.0(6) A 3 , Z = 2. Ca and Fe 3+ occupy two large octahedra and two smaller octahedra, respectively. The strongest lines of the powder diffraction pattern [ d , A ( I , %) ( hkl )] are: 11.04 (100) (110), 4.432 (10) (021), 4.133 (6) (22-1), 3.754 (4) (240), 3.486 (11) (400), 2.636 (8) (35-1), 2.551 (4) (002), 2.505 (6) (26-1). Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, under registration number 4018/1.

Lahnsteinite, Zn4(SO4)(OH)6 · 3H2O, a new mineral from the Friedrichssegen Mine, Germany

A new mineral, lahnsteinite, has been found in the dump of the Friedrichssegen Mine, Bad Ems district, Rhineland-Palatinate (Rheinland-Pfalz), Germany. Lahnsteinite, occurring as colorless tabular crystals in the cavities of goethite, is associated with pyromorphite, hydrozincite, quartz, and native copper. The Mohs’ hardness is 1.5; the cleavage is perfect parallel to (001). Dcalc = 2.995 g/cm3, Dmeas = 2.98(2) g/cm3. The IR spectrum is given. The new mineral is optically biaxial, negative, α = 1.568(2), β = 1.612(2), γ = 1.613(2), 2Vmeas = 18(3)°, 2Vcalc = 17°. The chemical composition (wt %, electron microprobe data; H2O was determined by gas chromatography of ignition products) is as follows: 3.87 FeO, 1.68 CuO, 57.85 ZnO, 15.83 SO3, 22.3 H2O, total is 101.53. The empirical formula is (Zn3.3Fe0.27Cu0.11)Σ3.91(S0.98O4)(OH)5 · 3H2.10O. The crystal structure has been studied on a single crystal. Lahnsteinite is triclinic, space group P1, a = 8.3125(6), b = 14.545(1), c = 18.504(2) Å, α = 89.71(1), β = 90.05(1), γ = 90.13(1)°, V = 2237.2(3) Å3, Z = 8. The strong reflections in the X-ray powder diffraction pattern [d, Å (I, %)] are: 9.30 (100), 4.175 (18), 3.476 (19), 3.290 (19), 2.723 (57), 2.624 (36), 2.503 (35), 1.574 (23). The mineral has been named after its type locality near the town of Lahnstein. The type specimen of lahnsteinite is deposited in the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, registration number 4252/1.

Hydroxymanganopyrochlore: A new mineral from the Eifel volcanic region, Germany

cubic (usually with the space group Fd m, a ≈ 10.4 Å, Z = 8) complex oxides with a simplified general for mula A2B2X6Y, where B are 3 , 4 , 5 , or 6 valent cat ions forming the octahedral framework (the primary ones of them are Ta5+ (microlite group), Nb5+ (pyro chlore group), Ti4+ (betafite group), Sb5+ (romeite group), and W6+ (elsmoreite group)); A are the extraframework cations (the primary ones of them are Na+, Ca2+, Sr2+, Ba2+, Pb2+, REE3+, and U4+) or H2O molecules; X anions are usually represented by O2–, whereas Y = OH–, F–, H2O, or O 2–. A, X, and Y sites may be vacant in part. Manganese in natural samples was previously observed as a small admixture (presum ably Mn2+ in A site) [2, 3]. In this paper we report the Mn2+ dominant mineral of the pyrochlore super group, which was approved by the Commission on New Minerals, Nomenclature, and Classification of the International Mineralogical Association as a new mineral species called hydroxymanganopyrochlore (IMA No. 2012 005).

Perrierite-(La), (La,Ce,Ca)4(Fe2+,Mn)(Ti,Fe3+,Al)4(Si2O7)2O8, a new mineral species from the Eifel volcanic district, Germany

Non-metamict perrierite-(La) discovered in the Dellen pumice quarry, near Mendig, in the Eifel volcanic district, Rheinland-Pfalz, Germany has been approved as a new mineral species (IMA no. 2010-089). The mineral was found in the late assemblage of sanidine, phlogopite, pyrophanite, zirconolite, members of the jacobsite-magnetite series, fluorcalciopyrochlore, and zircon. Perrierite-(La) occurs as isolated prismatic crystals up to 0.5 × 1 mm in size within cavities in sanidinite. The new mineral is black with brown streak; it is brittle, with the Mohs hardness of 6 and distinct cleavage parallel to (001). The calculated density is 4.791 g/cm3. The IR spectrum does not contain absorption bands that correspond to H2O and OH groups. Perrierite-(La) is biaxial (-), α = 1.94(1), β = 2.020(15), γ = 2.040(15), 2Vmeas = 50(10)°, 2Vcalc = 51°. The chemical composition (electron microprobe, average of seven point analyses, the Fe2+/Fe3+ ratio determined from the X-ray structural data, wt %) is as follows: 3.26 CaO, 22.92 La2O3, 19.64 Ce2O3, 0.83 Pr2O2, 2.09 Nd2O3, 0.25 MgO, 2.25 MnO, 3.16 FeO, 5.28 Fe2O3, 2.59 Al2O3, 16.13 TiO2, 0.75 Nb2O5, and 20.06 SiO2, total is 99.21. The empirical formula is (La1.70Ce1.45Nd0.15Pr0.06Ca0.70)Σ4.06(Fe0.532+Mn0.38Mg0.08)Σ0.99(Ti2.44Fe0.803+Al0.62Nb0.07)Σ3.93Si4.04O22. The simplified formula is (La,Ce,Ca)4(Fe2+,Mn)(Ti,Fe3+,Al)4(Si2O7)2O8. The crystal structure was determined by a single crystal. Perrierite-(La) is monoclinic, space group P21/a, and the unit-cell dimensions are as follows: a =13.668(1), b = 5.6601(6), c = 11.743(1) Å, β = 113.64(1)°; V = 832.2(2) Å3, Z = 2. The strong reflections in the X-ray powder diffraction pattern are [d, Å (I, %) (hkl)]: 5.19 (40) (110), 3.53 (40) (

Ferroindialite (Fe2+,Mg)2Al4Si5O18, a new beryl-group mineral from the Eifel volcanic region, Germany

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Wernerkrauseite, CaFe3+2Mn4+O6–the first nonstoichiometric post-spinel mineral, from Bellerberg volcano, Eifel, Germany

11), 2.96 (100) (

Mineralogia ligure 2007-2008: novità caratterizzate dal servizio UK dell'AMI

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