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1.
Galgenbergite-(Ce) from the type locality, the railroad tunnel Galgenberg between Leoben and St. Michael, Styria, Austria, was investigated. There it occurs in small fissures of an albite-chlorite schist as very thin tabular crystals building rosette-shaped aggregates associated with siderite, ancylite-(Ce), pyrite and calcite. Electron microprobe analyses gave CaO 9.49, Ce2O3 28.95, La2O3 11.70, Nd2O3 11.86, Pr2O3 3.48, CO2 30.00, H2O 3.07, total 98.55 wt.%. CO2 and H2O calculated by stoichiometry. The empirical formula (based on Ca + REE ∑3.0) is $ \mathrm{C}{{\mathrm{a}}_{1.00 }}{{\left( {\mathrm{C}{{\mathrm{e}}_{1.04 }}\mathrm{L}{{\mathrm{a}}_{0.42 }}\mathrm{N}{{\mathrm{d}}_{0.42 }}\mathrm{P}{{\mathrm{r}}_{0.12 }}} \right)}_{2.00 }}{{\left( {\mathrm{C}{{\mathrm{O}}_3}} \right)}_4}\cdot {{\mathrm{H}}_2}\mathrm{O} $ , and the simplified formula is $ \mathrm{CaC}{{\mathrm{e}}_2}{{\left( {\mathrm{C}{{\mathrm{O}}_3}} \right)}_4}\cdot {{\mathrm{H}}_2}\mathrm{O} $ . According to X-ray single crystal diffraction galgenbergite-(Ce) is triclinic, space group $ P\overline{1},a=6.3916(5) $ , b?=?6.4005(4), c?=?12.3898(9) Å, α?=?100.884(4), β?=?96.525(4), γ?=?100.492(4)°, V?=?483.64(6) Å3, Z?=?2. The eight strongest lines in the powder X-ray diffraction pattern are [d calc in Å/(I)/hkl]: 5.052/(100)/011; 3.011/(70)/0-22; 3.006/(66)/004; 5.899/(59)/-101; 3.900/(51)/1-12; 3.125/(46)/-201; 2.526/(42)/022; 4.694/(38)/-102. The infrared absorption spectrum reveals H2O (OH-stretching mode at 3,489 cm?1, HOH bending mode at 1,607 cm?1) and indicates the presence of distinctly non-equivalent CO3-groups by double and quadruple peaks of their ν1, ν2, ν3 and ν4 modes. The crystal structure of galgenbergite-(Ce) was refined with X-ray single crystal data to R1?=?0.019 for 2,448 unique reflections (I?>?2σ(I)) and 193 parameters. The three cation sites of the structure Ca(1), Ce(2) and Ce(3) have a modest mixed site occupation by Ca and small amount of REE (Ce, La, Pr, Nd) and vice versa. The structure is based on double layers parallel to (001), which are composed of Ca(1)Ce(2)(CO3)2 single layers with an ordered chessboard like arrangement of Ca and Ce, and with a roof tile-like stacking of the CO3 groups. Perpendicular to (001) the double layers are connected to a triclinic framework structure with good cleavage parallel to (001) by a differently organized and more open part of the structure formed by Ce(3)(CO3)2(H2O). Based on the topology of the CaCe(CO3)2 single layer in galgenbergite-(Ce), structural relationships to rutherfordine, to aragonite and ancylite type minerals, and to lanthanite are outlined.  相似文献   

2.
Summary The crystal structures of copper-substituted manganese-denningites, Mn(Mn1–x Cu x )(Te2O5)2 (0 x 1), were refined in space groupP42/nbc from single-crystal X-ray data. Single crystals with different degree of Cu-substitution suitable for X-ray investigation were synthesized under hydrothermal conditions, varying the Cu/Mn ratio and thepH-value. One main feature of the crystal structure is the distribution of Mn and Cu atoms among an eight and a six-coordinated site, respectively. Bond strength calculations support the site occupancies of the MnO8-polyhedra and MeO6-octahedra (Me = Cu., Mn1–x ). The decrease in length of the four Me[6]-O bonds clearly correlates with the increase of the Cu-substitution resulting in a distortion of the octahedra according to the Jahn-Teller effect of divalent copper. The stronger decrease of the lattice parameterc as compared toa is probably due to the variations of the bond lengths.
Kupfer-substituierte Mangan-Denningite, Mn(Mn1–x Cu x )(Te2O5)2 (0 x 1): Synthese und Kristallchemie
Zusammenfassung Die Kristallstrukturen von Kupfer-substituierten Mangan-Denningiten, Mn(Mn–x Cu x )(Te2O5)2 (0 x 1) wurden mittels Einkristall-Röntgenbeugungsdaten in der RaumgruppeP42/nbc verfeinert. Geeignete Einkristalle mit unterschiedlich starker Cu-Substitution wurden unter hydrothermalen Bedingungen durch Variieren des Cu/Mn-Verhältnisses bzw. despH-Wertes dargestellt. Ein wesentlicher struktureller Gesichtspunkt ist die Verteilung der Mn und Cu-Atome auf eine acht- bzw. sechskoordinierte Punktlage. Die Verringerung von vier Me[6]-O Bindungslängen ist klar korrelierbar mit zunehmender Cu-Substitution, und führt zu einer Verzerrung der Oktaeder gemäß dem für zweiwertiges Kupfer bekannten Jahn-Teller Effekt. Bindungsstärkenberechnungen belegen die Besetzung der MnO8-Polyeder und MeO6-Oktaeder (Me = Cu x Mn1–x ). Die bevorzugte Verkleinerung der Gitterkonstantec gegenübera kann auf die Variationen der Bindungslängen zurückgeführt werden.

Dedicated to Prof Dr. Josef Zemann on the occasion of his 70th birthday

With 10 Figures  相似文献   

3.
Doklady Earth Sciences - Sergeysmirnovite, MgZn2(PO4)2 · 4H2O, is a new mineral from the oxidation zone of the Kester mineral deposit, Sakha-Yakutia, Russia. This mineral forms...  相似文献   

4.
以固相反应合成了LiAlNb2O7,并用离子交换法制备出HAlNb2O7,通过紫外光分解等反应将Pt和TiO2分别掺杂到HAlNb2O7上。运用X射线衍射、漫反射、ICP和比表面积等测试技术对样品进行表征。在波长大于290 nm的100 W汞灯照射30 min下,1.0 g样品可催化分解甲醇溶液(10%)产生氢气约7 mL,表明所制备的材料具有较高的光催化活性。  相似文献   

5.
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). D calc = 2.174 g/cm3, D meas = 2.16(1) g/cm3. IR spectrum is given. Hillesheimite is biaxial (?), α = 1.496(2), β = 1.498(2), γ = 1.499(2), 2V meas = 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: K0.96Na0.08Ba0.16Ca0.56Mg0.58Fe 0.37 2+ [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.  相似文献   

6.
采用等温蒸发法研究简单四元体系Na ∥Cl-,CO32-,B4O72--H2O273K时的介稳相平衡,并测定该体系273K平衡液相中各组分的溶解度及密度,该体系的介稳相图和密度组成图显示:该四元体系在273K时的相图由3条溶解度单变量线、3个结晶区及1个共饱和点组成。体系属简单共饱型,无复盐或固溶体形成,3个结晶区分别对应单盐Na2CO3·10H2O,NaCl和Na2B4O7·10H2O。共饱点E处于Na2CO3·10H2O,NaCl及Na2B4O7·10H2O3盐共饱和,所对应的平衡液相组成为w(Na2CO3)=6.81%,w(NaCl)=21.69%,w(Na2B4O7)=0.65%,w(H2O)=70.85%。研究体系在273K下,Na2CO3·10H2O是碳酸钠盐的唯一析出形式,且硼酸钠对碳酸钠有盐析作用。  相似文献   

7.
Britvinite, a new mineral species, has been found in manganese ore at the Långban deposit, Bergslagen ore district, Filipstad, Värmland County, Sweden. Calcite, barytocalcite, brucite, cerussite, and hausmannite are associated minerals. Britvinite occurs as pale yellow to colorless transparent plates with a white streak up to 0.2 × 0.5 × 0.5 mm in size, which are flat parallel to {001}; the luster is adamantine. Thin lamellae are flexible, whereas thick ones are brittle; the Mohs hardness is 3. The cleavage is eminent parallel to {001}. The calculated density is 5.51 g/cm3. In the infrared spectrum of the new mineral, the bands of (OH)?, (CO3)2?, and (BO3)3? are recorded, whereas those corresponding to water molecules are absent. Britvinite is optically biaxial and negative, α = 1.896(2), β = 1.903(2), γ = 1.903(2), 2Vmeas = 20(10), Z≈c. Dispersion is strong, r<v. The chemical composition (electron microprobe; H2O determined with the Alimarin method, CO2, with selective sorption) is (wt %) 7.95 MgO, 71.92 PbO, 0.41 Al2O3, 12.77 SiO2, 2.2 H2O, 2.1 CO2, 2.67 B2O3 (calculated on the basis of structural data); total 100.02. The empirical formula calculated on the basis of 59 anions (O + OH) (Z = 1) is as follows: Pb14.75Mg9.03Si9.73Al0.37O30.76(BO3)3.51(CO3)2.18(OH)11.7. The simplified formula (Z = 2) is Pb7 + x Mg4.5(Si5O14)(BO3)2(CO3)(OH,O)7 (x < 0.5). The crystal structure of britvinite has been studied on a single crystal at 173 K; R = 0.0547. The new mineral is triclinic, space group P $ \bar 1 Britvinite, a new mineral species, has been found in manganese ore at the L?ngban deposit, Bergslagen ore district, Filipstad, V?rmland County, Sweden. Calcite, barytocalcite, brucite, cerussite, and hausmannite are associated minerals. Britvinite occurs as pale yellow to colorless transparent plates with a white streak up to 0.2 × 0.5 × 0.5 mm in size, which are flat parallel to {001}; the luster is adamantine. Thin lamellae are flexible, whereas thick ones are brittle; the Mohs hardness is 3. The cleavage is eminent parallel to {001}. The calculated density is 5.51 g/cm3. In the infrared spectrum of the new mineral, the bands of (OH)−, (CO3)2−, and (BO3)3− are recorded, whereas those corresponding to water molecules are absent. Britvinite is optically biaxial and negative, α = 1.896(2), β = 1.903(2), γ = 1.903(2), 2Vmeas = 20(10), Z≈c. Dispersion is strong, r<v. The chemical composition (electron microprobe; H2O determined with the Alimarin method, CO2, with selective sorption) is (wt %) 7.95 MgO, 71.92 PbO, 0.41 Al2O3, 12.77 SiO2, 2.2 H2O, 2.1 CO2, 2.67 B2O3 (calculated on the basis of structural data); total 100.02. The empirical formula calculated on the basis of 59 anions (O + OH) (Z = 1) is as follows: Pb14.75Mg9.03Si9.73Al0.37O30.76(BO3)3.51(CO3)2.18(OH)11.7. The simplified formula (Z = 2) is Pb7 + x Mg4.5(Si5O14)(BO3)2(CO3)(OH,O)7 (x < 0.5). The crystal structure of britvinite has been studied on a single crystal at 173 K; R = 0.0547. The new mineral is triclinic, space group P ; the unit-cell dimensions are a = 9.3409(8), b = 9.3597(7), c = 18.8333(14) ?, α = 80.365(6)°, β = 75.816(6)°, γ = 59.870(5)°, V = 1378.74(19) ?3. The structure consists of alternating TOT stacks (containing octahedral brucite-like and discontinuous tetrahedral (Si5O14)∞∞ layers) and multilayered [Pb7.1(OH)3.6(CO3)(BO3)1.75(SiO4)0.25]∞∞ blocks. The strongest reflections in the X-ray powder diffraction pattern [d, ? (I, %)(hkl)] are 18.1(100)(001), 3.39(30)(12, 14, 015), 3.02(90)(006, 130, 106, 20, 11), 2.698(70)(332, 134, 030, 1), 2.275(30)(008, 420, 424), 1.867(30)(446, 239, 2.1.10, 18), 1.766(40)(151, 31, 10, 453, 542, 512, 42), 1.519(40)(0.0.12). The mineral has been named in honor of Sergei Nikolaevich Britvin (b. 1965), a Russian mineralogist. The type material of britvinite is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow. The registration number is 3458/1. Original Russian Text ? N.V. Chukanov, O.V. Yakubovich, I.V. Pekov, D.I. Belakovsky, W. Massa, 2007, published in Zapiski Rossiiskogo Mineralogicheskogo Obshchestva, 2007, Pt CXXXVI, No. 6, pp. 18–25. The new mineral britvinite and its name were accepted by the Commission on New Minerals and Mineral Names, Russian Mineralogical Society, June 7, 2006, and approved by the Commission on New Minerals and Mineral Names, International Mineralogical Association, October 17, 2006.  相似文献   

8.
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9.
The heat capacity of åkermanite solid solutions was measured by a small scale adiabatic calorimeter near the incommensurate-normal (I-N) transition. The heat capacity anomalies caused by the I-N transition show the type characteristic behavior implying the presence of dynamical fluctuations. The heat capacity anomalies were observed over the whole range of the åkermanite solid solutions Ca2Mg1-xCoxSi2O7 and Ca2Mg1-x-ZnxSi2O2. With increase of Co or Zn atoms, the transition temperature, Ti, rises linearly from ca. 83° C to 220° C and to 130° C, respectively. In the system Ca2CoSi2O7-Ca2FeSi2O7 and Ca2MgSi2O7-Ca2-FeSi2O7 electronic microscopy revealed that the temperature of the heat capacity anomaly decreases with increasing Fe content, whereas the Ti rises. This unusual behavior is ascribed to the microdomains observed in high resolution lattice images.  相似文献   

10.
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11.
A new mineral aklimaite, Ca4[Si2O5(OH)2](OH)4 · 5H2O, has been found near Mount Lakargi, Upper Chegem caldera, Kabardino-Balkaria, the Northern Caucasus, Russia, in the skarnified limestone xenolith in ignimbrite. This hydrothermal mineral occurs in a cavity of altered larnite skarn and is associated with larnite, calcium humite-group members, hydrogarnets, bultfonteinite, afwillite, and ettringite. Aklimaite forms transparent, colorless (or occasionally with pinkish tint) columnar or lath-shaped crystals up 3 × 0.1 × 0.01 mm in size, flattened on {001} and elongated along {010}; they are combined in spherulites. The luster is vitreous; the cleavage parallel to the {001} is perfect. D calc = 2.274 g/cm3. The Mohs’ hardness is 3–4. Aklimaite is optically biaxial, negative, 2V meas > 70°, 2V calc = 78°, α = 1.548(2), β = 1.551(3), γ = 1.553(2). The IR and Raman spectra are given. The chemical composition (wt %, electron microprobe) is as follows: 0.06 Na2O, 0.02 K2O, 45.39 CaO, 0.01 MnO, 0.02 FeO, 24.23 SiO2, 0.04 SO3, 3.22 F, 27.40 H2O(calc.), ?1.36 -O=F2; the total is 99.03. The empirical formula calculated on the basis of 2Si apfu with O + OH + F = 16 is as follows: (Ca4.02Na0.01)Σ4.03[Si2.00O5.07(OH)1.93][(OH)3.16F0.84] Σ4.00 · 5H2O. The mineral is monoclinic, space group C2/m, a = 16.907(5), b = 3.6528(8), c = 13.068(4) Å, β = 117.25(4)·, V= 717.5(4) Å3, Z = 2. Aklimaite is representative of the new structural type, the sorosilicate with disilicate groups [Si2O5(OH)2]. The strongest reflections in the X-ray powder patterns [d, Å (hkl)] are: 11.64(100)(001), 2.948(32)(310, 203), 3.073(20) ( $\bar 404$ , $\bar 311$ ), 2.320(12)(005, 510), 2.901 (11)(004), 8.30(10) $\left( {\bar 201} \right)$ . The type specimen is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow.  相似文献   

12.
Mössbauer spectra (MS) of anapaite (Ca2 Fe2+(PO4)2?·?4H2O) and of a sample after being immersed in a 4% H2O2 solution at room temperature (RT) over 12 days (hereafter an4ox) were collected at temperatures in the range 4.2 to 420?K and 11 to 300?K respectively. All MS consist of symmetrical doublets, hence magnetic ordering was not observed. The temperature dependencies of the Fe2+ centre shifts of anapaite and an4ox were analysed with the Debye model for the lattice vibrations. The characteristic Mössbauer temperatures were found as 370?K?±?25?K and 340?K?±?25?K, and the intrinsic isomer shifts as 1.427?±?0.005?mm/s and 1.418?±?0.005?mm/s respectively. From the external-field (60?kOe) MS recorded at 4.2 and 189?K for the non-treated sample, the principal component V zz of the electric field gradient (EFG) is determined to be positive and the asymmetry parameter η?≈?0.2 and 0.4 respectively. The temperature variations of the quadrupole splittings, ΔE Q(T), cannot be interpreted on the basis of the thermal population of the 5 D electronic levels resulting from the tetragonal compression of the O6 co-ordination. The low-temperature linear behaviour of ΔE Q(T) is attributed to a strong orbit-lattice coupling. A field of 60 kOe applied to anapaite at 4.2?K produces magnetic hyperfine splitting with effective hyperfine fields of ?136, ?254 and ?171?kOe along the principal axes Ox, Oy and Oz of the EFG tensor respectively. Additional oxidation treatments in solutions with various H2O2 concentrations up to 20% and subsequent Mössbauer experiments at room temperature, have revealed that the anapaite structure is not sensitive to oxidation since eventually only a small amount of Fe2+ (～6.5%) is converted into Fe3+.  相似文献   

13.
The structural behavior under pressure of three lanthanide pyrochlore zirconates Ln2Zr2O7 (Ln3+ = Ce, Nd and Gd) has been investigated by X-ray diffraction up to 50 GPa. For all three compounds, a symmetry reduction from cubic to monoclinic is observed under increasing pressure dependant on a pressure value that increases with the ionic radius of the lanthanide ions, r Ln. The cubic and monoclinic phases coexist over a wide pressure range which increases with r Ln. The zero-pressure bulk modulus of the cubic phase, B 0, and its pressure derivative, B 0′, have been determined by fitting the experimental compressibility curves to the Birch–Murnaghan equation of state.  相似文献   

14.
Geology of Ore Deposits - Epifanovite, NaCaCu5(PO4)4[AsO2(OH)2] · 7H2O, a new natural copper, sodium and calcium arsenate–phosphate, has been found in a quartz–phosphate pocket...  相似文献   

15.
A new mineral, günterblassite, has been found in the basaltic quarry at Mount Rother Kopf near Gerolstein, Rheinland-Pfalz, Germany as a constituent of the late assemblage of nepheline, leucite, augite, phlogopite, åkermanite, magnetite, perovskite, a lamprophyllite-group mineral, götzenite, chabazite-K, chabazite-Ca, phillipsite-K, and calcite. Günterblassite occurs as colorless lamellar crystals up to 0.2 × 1 × 1.5 mm in size and their clusters. The mineral is brittle, with perfect cleavage parallel to (001) and less perfect cleavage parallel to (100) and (010). The Mohs hardness is 4. The calculated and measured density is 2.17 and 2.18(1) g/cm3, respectively. The IR spectrum is given. The new mineral is optically biaxial and positive as follows: α = 1.488(2), β = 1.490(2), γ = 1.493(2), 2V meas = 80(5)°. The chemical composition (electron microprobe, average of seven point analyses, H2O is determined by gas chromatography, wt %) is as follows: 0.40 Na2O, 5.18 K2O, 0.58 MgO, 3.58 CaO, 4.08 BaO, 3.06 FeO, 13.98 Al2O3, 52.94 SiO2, 15.2 H2O, and the total is 98.99. The empirical formula is Na0.15K1.24Ba0.30Ca0.72Mg0.16F 0.48 2+ [Si9.91Al3.09O25.25(OH)3.75] · 7.29H2O. The crystal structure has been determined from a single crystal, R = 0.049. Günterblassite is orthorhombic, space group Pnm21; the unit-cell dimensions are a = 6.528(1), b = 6.970(1), c = 37.216(5) Å, V = 1693.3(4) Å3, Z = 2. Günterblassite is a member of a new structural type; its structure is based on three-layer block [Si13O25(OH,O)4]. The strong reflections in the X-ray powder diffraction pattern [d Å (I, %) are as follows: 6.532 (100), 6.263 (67), 3.244 (49), 3.062 (91), 2.996 (66), 2.955 (63), and 2.763 (60). The mineral was named in honor of Günter Blass (born in 1943), a well-known amateur mineralogist and specialist in electron microprobe and X-ray diffraction. The type specimen of günterblassite is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, with the registration number 4107/1.  相似文献   

16.
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17.
The water-pressure and temperature stability fields of clinohumite-OH, chondrodite-OH and phase A were determined in reversed equilibrium experiments up to 100 kbar within the system MgO–SiO2–H2O. Their PT-fields differ from results from former synthesis experiments. Bracketing experiments on the reaction phase A + low P-clinoenstatite ⇆ forsterite + water resulted in a slightly steeper dP/dT-slope compared to earlier experiments for this equilibrium. Clinohumite-OH and chondrodite-OH both have large stability fields which extend over pressure ranges of more than 80 kbar. However, they are hardly relevant as hydrous minerals within the subducted oceanic lithosphere. Both are too Mg-rich for a typical mantle bulk composition. In addition, the dehydration of subducted oceanic lithosphere – due to (forsterite + water)-forming reactions – will occur before the two humite-group phases even become stable. Restricted to the cool region of cold subducting slabs, phase A, however, might be formed via the reactions phase A + low P-/high P-clinoenstatite ⇆ forsterite + water or antigorite + brucite ⇆ phase A + water, before dehydration of the oceanic lithosphere occurs. Received: 22 July 1997 / Accepted: 12 March 1998  相似文献   

18.
采用等温溶解平衡法研究了288K时Li+,Mg2+//SO42-,B4O72--H2O四元体系的固液相平衡关系,测定了该四元体系在288K时平衡液相的溶解度和密度。依据实验测定的平衡溶解度数据及对应的平衡固相,绘制了该四元体系的平衡相图及密度组成图。研究结果表明:交互四元体系Li+,Mg2+//SO42-,B4O27--H2O288K时平衡相图中有2个共饱点,5条单变量曲线,4个结晶区对应的平衡固相分别为Li2B4O7.3H2O,Li2SO4.H2O,MgB4O7.9H2O和MgSO4.7H2O。  相似文献   

19.
Summary Niedermayrite, Cu4Cd(SO4)2(OH)6 · 4H2O, is a new mineral discovered in 1995 in the Km3-area of the Lavrion mining district, Greece. It forms tiny euhedral plates, commonly intergrown as green crusts up to several cm2 in size on a matrix consisting of a brecciated marble with sphalerite, chalcopyrite, galena, greenockite, hawleyite and pyrite. Associated secondary minerals are gypsum, malachite, chalcanthite, brochantite, hemimorphite, hydrozincite, aurichalcite, one unknown Cd-sulfate, monteponite and otavite. Niedermayrite is non-fluorescent and has a bluish-green colour with vitreous lustre, the streak is white. The crystals are brittle with perfect cleavage parallel {010}. Optics: biaxial (–) with n(calc.), n, and n =1.609, 1.642(2), and 1.661(2), respectively; orientation n//b. The calculated density is 3.292 gcm–3. The most prominent form is {010}. Analysis by electron microprobe gives CdO 16.5, CuO 45.7, SO3 21.6, H2O 16.2 wt.% (calc. to 100% sum) and the empirical formula Cu4.29Cd0.96S2.01O11.28 · 6.71 H2O (based on 18 oxygens p.f.u.). By TGA an H2O content of 18.9 wt.% was obtained. The ideal formula (confirmed by the crystal structure refinement) is Cu4Cd(SO4)2(OH)6 · 4H2O with a theoretical H2O content of 17.2 wt.%. The strongest lines in the X-ray powder diffraction pattern (Gandolfi camera, visually estimated I, refined lattice parameters a = 5.535(2), b = 21.947(9), c = 6.085(2) Å, = 91.98(3)°) are: (dobs[Å]/Iobs/hkl) (11.02/90/0 2 0), (5.874/20/0 1 1), (5.496/100/0 4 0), (5.322/25/0 2 1), (4.079/50/0 4 1), (3.660/20/0 6 0), (3. 437/30/1 5 0), (3.243/40/1 4 1), (2.470/30/2 4 0), (2.425/20/1 4 –2), (2.205/20/2 6 0) and (1.897/20/1 8 2). The mineral is monoclinic, P21/m, Z = 2, a = 5.543(1) Å, b = 21.995(4) Å, c = 6.079(1) Å, = 92.04(3)°, V = 740.7(2) Å3. The crystal structure was determined by single crystal X-ray methods and was refined to R1= 0.026, wR2 = 0.056. The structure of niedermayrite is characterized by 2 [Cu4(OH)6O2]2– sheets of edgesharing Cu coordination octahedra parallel to (010) with attached SO4 tetrahedra, and intercalated CdO2(H2O)4 octahedra with a system of hydrogen bonds. Close relationships to the crystal structures of christelite and campigliaite exist. The new mineral is named for Dr. Gerhard Niedermayr, Naturhistorisches Museum Wien, Austria.
Niedermayrit, Cu4Cd(SO4)2(OH)6 · 4H2O, ein neues Mineral aus dem Bergbaugebiet Lavrion, Griechenland
Zusammenfassung Niedermayrit, Cu4Cd(SO4)2(OH)6 · 4H2O, ist ein neues Mineral, das 1995 im Km3-Bereich des Bergbaugebietes Lavrion, Griechenland, gefunden wurde. Es bildet winzige gut ausgebildete Plättchen, häufig miteinander verwachsen in grünen Krusten bis zu mehreren cm2 Größe. Die Matrix besteht aus brecciösem Marmor mit Sphalerit, Chalcopyrit, Galenit, Greenockit, Hawleyit und Pyrit. Sekundäre Begleitminerale sind Gips, Malachit, Chalcanthit, Brochantit, Hemimorphit, Hydrozincit, Aurichalcit, ein unbekanntes Cd-Sulfat, Monteponit und Otavit. Niedermayrit fluoresziert nicht, besitzt blaugrüne Farbe mit Glasglanz, der Strich ist weiß. Die Kristalle sind spröd mit perfekter Spaltbarkeit parallel {010}. Optik: biaxial (–) mit n(ber.), n, und n=1.609, 1.642(2), und 1.661(2); Orientierung n//b. Die berechnete Dichte beträgt 3.292 gcm–3. Die auffallendste Flächenform ist {010}. Die chemische Analyse mittels Mikrosonde ergibt CdO 16.5, CuO 45.7, SO3 21.6, H2O 16.2wt.% (ber. auf 100% Summe) und die empirische Formel Cu4.29Cd0.96S2.01O11.28 · 6.71 H2O (basierend auf 18 Sauerstoffatomen pro Formeleinheit). Aus der TGA wurde ein H2O Gehalt von 18.9 Gew.% erhalten. Die Idealformel (bestätigt durch die Kristallstrukturverfeinerung) ist Cu4Cd(SO4)2(OH)6 · 4H2O bei einem theoretischen H2O-Gehalt von 17.2 Gew.%. Die stärksten Linien im Pulverdiffraktogramm (Gandolfi Kamera, visuell geschätzte I, verfeinerte Gitterkonstanten a = 5.535(2), b = 21.947(9), c = 6.085(2) Å, = 91.98(3)°) sind: (dobs[Å]/Iobs/hkl) (11.02/90/0 2 0), (5.874/20/0 1 1), (5.496/100/0 4 0), (5.322/25/0 2 1), (4.079/50/0 4 1), (3.660/20/0 6 0), (3.437/30/1 5 0), (3.243/40/1 4 1), (2.470/30/2 4 0), (2.425/20/1 4 –2), (2.205/20/2 6 0) und (1.897/20/1 8 2). Das Mineral ist monoklin, P21/m, Z = 2, a = 5.543(1) Å, b = 21.995(4) Å, c = 6.079(1) Å, = 92.04(3)°, V = 740.7(2) Å3 Die Kristallstruktur wurde mittels Einkristallröntgenmethoden bestimmt und zu R1 = 0.026, wR2 = 0.056 verfeinert. Die Struktur von Niedermayrit ist durch 2 [Cu4(OH)6O2]2– Schichten von kantenverknüpften Cu-Koordinationsoktaedern parallel (010) gekennzeichnet mit damit verbundenen SO4 Tetraedern und dazwischen befindlichen CdO2(H2O)4 Oktaedem mit einem Wasserstoffbrückensystem. Es bestehen enge Beziehungen mit den Kristallstrukturen von Christelit und Campigliait. Das neue Mineral ist nach Dr. Gerhard Niedermayr, Naturhistorisches Museum Wien, Österreich, benannt.

With 7 Figures  相似文献   

20.
A new mineral kobyashevite, Cu5(SO4)2(OH)6·4H2O (IMA 2011–066), was found at the Kapital’naya mine, Vishnevye Mountains, South Urals, Russia. It is a supergene mineral that occurs in cavities of a calcite-quartz vein with pyrite and chalcopyrite. Kobyashevite forms elongated crystals up to 0.2 mm typically curved or split and combined into thin crusts up to 1?×?2 mm. Kobyashevite is bluish-green to turquoise-coloured. Lustre is vitreous. Mohs hardness is 2½. Cleavage is {010} distinct. D(calc.) is 3.16 g/cm3. Kobyashevite is optically biaxial (?), α 1.602(4), β 1.666(5), γ 1.679(5), 2 V(meas.) 50(10)°. The chemical composition (wt%, electron-microprobe data) is: CuO 57.72, ZnO 0.09, FeO 0.28, SO3 23.52, H2O(calc.) 18.39, total 100.00. The empirical formula, calculated based on 18 O, is: Cu4.96Fe0.03Zn0.01S2.01O8.04(OH)5.96·4H2O. Kobyashevite is triclinic, $ P\overline{\,1 } $ , a 6.0731(6), b 11.0597(13), c 5.5094(6)?Å, α 102.883(9)°, β 92.348(8)°, γ 92.597(9)°, V 359.87(7)?Å3, Z?=?1. Strong reflections of the X-ray powder pattern [d,Å-I(hkl)] are: 10.84–100(010); 5.399–40(020); 5.178–12(110); 3.590–16(030); 2.691–16(20–1, 040, 002), 2.653–12(04–1, 02–2), 2.583–12(2–11, 201, 2–1–1), 2.425–12(03–2, 211, 131). The crystal structure (single-crystal X-ray data, R?=?0.0399) сontains [Cu4(SO4)2(OH)6] corrugated layers linked via isolated [CuO2(H2O)4] octahedra; the structural formula is CuCu4(SO4)2(OH)6·4H2O. Kobyashevite is a devilline-group member. It is named in memory of the Russian mineralogist Yuriy Stepanovich Kobyashev (1935–2009), a specialist on mineralogy of the Urals.  相似文献   

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