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1.
A new mineral species, named naquite(FeSi), is found in the podiform chromitites of the Luobusha ophiolite in Qusong County, Tibet, China. The detailed composition is Fe 65.65, Si 32.57 and Al 1.78 wt%. The mineral is cubic, space group P213. The irregular crystals range from 15 to 50 μm in diameter and form an intergrowth with luobusaite. Naquite is steel grey in color, opaque, with a metallic lustre and gives a grayish-black streak. The mineral is brittle, has a conchoidal fracture and no apparent cleavage. The estimated Mohs hardness is 6.5, and the calculated density is 6.128 g/cm3. Unit-cell parameters are a 4.486 (4) ?, V 90.28 (6) ?3, Z=4. The five strongest powder diffraction lines [d in ? (hkl) (I/I0)] are: 3.1742 (110) (40), 2.5917(111) (43), 2.0076 (210) (100), 1.8307 (211) (65), and 1.1990 (321) (36). Originally called ‘fersilicite’, the species and new name have now been approved by the CNMNC (IMA 2010–010).  相似文献   

2.
Lisiguangite, CuPtBiS3, is a new mineral species discovered in a PEG-bearing, Co-Cu sulfide vein in garnet pyroxenite of the Yanshan Mountains, Chengde Prefecture, Hebei Province, China. It is associated with chalcopyrite and bornite, galena, minor pyrite, carrolite, molybdenite and the platinum-group minerals daomanite (CuPtAsS2), Co-bearing malanite (Cu(Pt, Co)2S4) sperrylite, moncheite, cooperite and malyshevite (CuPdBiS3), rare damiaoite (Pt2In3) and yixunite (Pt3In). Lisiguangite occurs as idiomorphic crystals, tabular or lamellae (010) and elongated [100] or as aggregates, up to 2 mm long and 0.5 mm wide. The mineral is opaque, has lead-gray color, black streak and metallic luster. The mineral is non-fluorescent. The observed morphology displays the following forms: pinacoids {100}, {010}, {001}, and prism {110}. No twining is observed. The a:b:c ratio, calculated from unit-cell parameters, is 0.6010:1:0.3836. Cleavage: {010} perfect, {001} distinct, {100} may be visible. H Mohs: 21/2; VHN25=46.7-49.8 (mean 48.3) kg/mm2. Tenacity: brittle. Lisiguangite is bright white with a yellowish tint. In reflected light it shows neither internal reflections nor bireflectance or pleochroism. It has weak to moderate anisotropy (blue-greenish to brownish) and parallel-axial extinction. The reflectance values in air (and in oil) for R3, R4 and (imR3, imR4), at the standard Commission on Ore Mineralogy wavelengths are: 37.5, 35.7 (23.4, 22.3) at 470 nm; 38.6, 36.5 (23.6, 22.6) at 546 nm; 39.4, 37.5 (23.6, 22.7) at 589 nm and 40.3, 38.2 (23.7, 22.9) at 650 nm. The average of eight electron-microprobe analyses: Cu 12.98, Pt 30.04, Pd 2.69, Bi 37.65 and S 17.55, totaling 100.91%, corresponding to Cu1.10(Pt 0.83, Pd0.14)Σ0.97Bi0.97S2.96 based on six atoms apfu. The ideal formula is CuPtBiS3. The mineral is orthorhombic. Space group: P212121, a=7.7152(15)?,b=12.838(3)?, c=4.9248(10)?, V=487.80(17)?3, Z=4. The six strongest lines in the X-ray powder-diffraction pattern [d in ? (I) (h k l) are 6.40(30)(020), 3.24(80)(031), 3.03(100)(201), 2.27(40)(051), 2.14(50)(250), 1.865(60)(232).  相似文献   

3.
Hydroxycalciopyrochlore, ideally(Ca,Na,U,□)2(Nb,Ti)2O6(OH), cubic, is a new mineral species(IMA2011-026) within the pyrochlore supergroup that was found occurring at the Maoniuping mine, Mianning County, Xichang prefecture, Sichuan Province, southwest China. The mineral is found in an alkali feldspar granite rare-earth ore deposit(26–27 Ma). Associated minerals include calcite, barite, celestine, albite, aegirine, aegirine-augite, fluorite, parasite-(Ce), thorite, thorianite, zircon, galena, sphalerite, magnetite, and pyrite. Crystals occur mostly as octahedra, and less often as dodecahedra and tetrahexahedra or combinations thereof. Some occur with an allotriomorphic habit with a thick triangular tabular form. Crystals generally range from 0.1 to 1 mm in size. The mineral is brownishblack, greenish-black and black on fresh sections with a brown streak. The crystal is translucent, and has a greasy lustre on fresh sections. It is metamict without any observed parting or cleavage and with a conchoidal fracture. The Vickers microhardness is 572 kg/mm2(5–6 on the Mohs hardness scale). The density measured by hydrostatic weighing is 5.10(3) g/cm3. The strongest four reflections in the X-ray powder-diffraction pattern [d in(I) hkl] are: 2.9657(100) 2 2 2, 1.8142(34) 0 4 4, 1.5463(21) 2 2 6, 2.5688(18) 0 0 4. The unit-cell parameters are a = 10.381(4), V = 1118.7(7)3, Z = 8. The structure was solved and refined in the space group Fd3m with R = 0.09. The empirical formula is(Ca0.74Na0.58U0.40Ce0.05Fe0.02□0.21)2.00(Nb1.15Ti0.80Ta0.03Al0.01Mg0.01)2.00O6.02 [(OH)1.01F0.09]1.10, on the basis of 2 atoms of B pfu; the simplified formula is(Ca,Na,U,□)2(Nb,Ti)2O6(OH). Type material is deposited in the Geological Museum of China, Beijing, People's Republic of China, catalogue number M11800.  相似文献   

4.
Yarlongite: A New Metallic Carbide Mineral   总被引:1,自引:0,他引:1  
Yarlongite occurs in ophiolitic chromitite at the Luobusha mine (29°5′N 92°5′E, about 200 km ESE of Lhasa), Qusum County, Shannan Prefecture, Tibet Autonomous Region, People’s Republic of China. Associated minerals are: diamond, moissanite, wüstite, iridium (“osmiridium”), osmium (“iridosmine”), periclase, chromite, native iron, native nickel, native chromium, forsterite, Cr-rich diopside, intermetallic compounds Ni-Fe-Cr, Ni-Cr, Cr-C, etc. Yarlongite and its associated minerals were handpicked from a large heavy mineral sample of chromitite. The metallic carbides associated with yarlongite are cohenite, tongbaite, khamrabaevite and qusongite (IMA2007-034). Yarlongite occurs as irregular grains, with a size between 0.02 and 0.06 mm, steel-grey colour, H Mohs: 5?-6. Tenacity: brittle. Cleavage: {0 0 1} perfect. Fracture: conchoidal. Chemical formula: (Cr4Fe4Ni)Σ9C4, or (Cr,Fe,Ni)Σ9C4, Crystal system: Hexagonal, Space Group: P63/mc, a = 18.839(2) ?, c = 4.4960 (9) ?, V = 745.7(2) ?3, Z = 6, Density (calc.) = 7.19 g/cm3 (with simplified formula). Yarlongite has been approved as a new mineral by the CNMNC (IMA2007-035). Holotype material is deposited at the Geological Museum of China (No. M11650).  相似文献   

5.
Abramovite, a new mineral species, has been found as fumarole crust on the Kudryavy volcano, Iturup Island, Kuriles, Russia. The mineral is associated with pyrrhotite, pyrite, würtzite, galena, halite, sylvite, and anhydrite. Abramovite occurs as tiny elongated lamellar crystals up to 1 mm long and 0.2 mm wide (average 300 × 50 μ m), which make up chaotic intergrowths in the narrow zone of fumarole crust formed at ~600°C. Most crystals are slightly striated along the elongation. The new mineral is silver gray, with a metallic luster and black streak. Under reflected light, abramovite is white with a yellowish gray hue. It has weak bireflectance; anisotropy is distinct without color effects. The chemical composition (electron microprobe) is as follows, wt %: 20.66 S, 0.98 Se, 0.01 Cu, 0.03 Cd, 11.40 In, 12.11 Sn, 37.11 Pb, 17.30 Bi; the total is 99.60. The empirical formula calculated on the basis of 12 atoms is Pb1.92Sn1.09In1.06Bi0.89(S6.90Se0.13)7.03. The simplified formula is Pb2SnInBiS7. The strongest eight lines in the X-ray powder pattern [d, Å (I)(hkl)] are 5.90(36)(100), 3.90(100)(111), 3.84(71)(112), 3.166(26)(114), 2.921(33)(115), 2.902(16)(200), 2.329(15)(214), 2.186(18)(125). The selected area electron diffraction (SAED) patterns of abramovite are quite similar to those of the homologous cylindrite series minerals. The new mineral is characterized by noncommensurate structure composed of regularly alternated pseudotetragonal and pseudohexagonal sheets. The structure parameters determined from the SAED patterns and X-ray powder diffraction data for pseudotetragonal subcell are: a = 23.4(3), b = 5.77(2), c = 5.83(1) Å, α = 89.1(5) °, β = 89.9(7)°, γ = 91.5(7)°, V = 790(8) Å3; for pseudohexagonal subcell: a = 23.6(3), b = 3.6(1), c = 6.2(1) Å, α = 91(2)°, β = 92(1)°, γ = 90(2)°, V = 532(10) Å3. Abramovite is triclinic, space group P(1). The new mineral is named in honor of Russian mineralogist Dmitry Abramov. The type material of abramovite has been deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow.  相似文献   

6.
1 Introduction Chevkinite groups can be assigned to the chevkinite-(Ce) subgroup and perrierite-(Ce) subgroup in accord with the angle β : β ≈ 100o for the chevkinite subgroup and β ≈ 113o for the perrierite subgroup. Chevkinite-(Ce), polykovite-(Ce) and Maoniupingite (new mineral No. 017 of 2003) belong to the former subgroup, while renjeite and matsubaraite belong to the latter group. As strontio-chevkinite is a Sr-analogue of perrierite, usually the natural chevkinite-(Ce) group min…  相似文献   

7.
It was not possible to carry out a complete analyses of crystal, as the experiment by Ding and Shi et al.. It's analysis precision R=0.25 or more big than this, which value are not satisfied for single crystal study, but we through many test and found the best: [R(int)=14.5%]. The final fullmatix least-squares refinement on F2 converged to R1=0.0791 and wR2=0.1864 for 704 observed reflections [I 3 2s(I)]. Daomanite is orthorhombic system, space group Cmc21, a=3.7520(8))?, b=15.844(4) ?, c=5.8516(12) ?, α=β=γ=90°. V=347.86(14)?3, Z=4. Daomanite chemical formula is Cu Pt AsS 2. Idealized composition Me+M2+M2+S2=CuS ·PtA s S. There is no other similar mineral in the world.  相似文献   

8.
Calcium and magnesium‐bearing sabugalite occurs as aggregations of yellowish platy crystals in veinlets or druses in conglomerate from the oxidized parts of the Tono uranium deposit, Central Japan. X‐ray powder diffractometry of this mineral has reflections consistent with previous powder diffraction data of sabugalite. It is included in the monoclinic system with space group C2/m and calculated cell parameters of a = 19.68Å, b = 9.89Å, c = 9.82Å α = γ = 90°, β‐96.93° and V = 1897.83Å3. Chemical analysis yields a formula of (Ca0.10 Mg0.09)Σ0.19Al0.53(UO2)2.04((PO4)1.99(AsO4)0.01)Σ2.00·11.22H2O. EMPA mapping shows that the mineral is compositionally uniform with no micron‐scale layering. Charge of cations including Ca and Mg in the cation‐H2O layer is 1.98 being identical to that of autunite group minerals. This suggests that the charge balance in the cation‐H2O layer of the mineral could be made by the alkaline earth or alkaline elements rather than by hydrogen ions.  相似文献   

9.
Bortnikovite, a new mineral species that is an intermetallic compound of Pd, Cu, and Zn with the simplified formula Pd4Cu3Zn has been detected at the unique Konder placer deposit in the Ayan-Maya district, Khabarovsk krai. The primary source of this placer is a concentrically zoned alkaline ultramafic massif. The X-ray diffraction pattern is indexed on the assumption of a tetragonal unit cell: a = 6.00 ± 0.02 Å and c = 8.50 ± 0.03 Å, V = 306 ± 0.01 Å3, Z = 3, probable space group P4/mmm. The calculated density is 11.16 g/cm3; the mean microhardness VHN is 368 kg/mm2. In reflected light, the new mineral is white with a slight grayish beige tint; bireflectance, anisotropy, and internal reflections are not observed. The reflectance spectrum belongs to the concave group of the anomalous type. The measured values of reflectance are as follows: 56.9 (470 nm), 61.7 (546 nm), 63.4 (589 nm), and 65.4% (650 nm). The new mineral is intergrown with isoferroplatinum, titanite, perovskite, V-bearing magnetite, bornite, and chlorite. The origin of bortnikovite is related to the effect of alkaline fluid on ultramafic rocks. The new mineral is named in honor of Professor Nikolai Stefanovich Bortnikov, a prominent mineralogist and researcher of ore deposits and a corresponding member of the Russian Academy of Sciences. Bortnikovite is the first platinum group mineral that contains Zn as a major mineralforming element.  相似文献   

10.
A new mineral, mariinskite, BeCr2O4, the chromium analog of chrysoberyl, has been found at the Mariinsky (Malyshevo) deposit, the Ural Emerald Mines, the Central Urals, Russia. The mineral is named after its type locality. It was discovered in chromitite in association with fluorphlogopite, Cr-bearing muscovite, eskolaite, and tourmaline. Mariinskite occurs as anhedral grains ranging from 0.01 to 0.3 mm in size; in some cases it forms pseudohexagonal chrysoberyl-type twins. The mineral is dark-green, with a pale green streak; the Mohs’ hardness is 8.5, microhardness VHN = 1725 kg/mm2. D meas = 4.25(2) g/cm3, D calc = 4.25 g/cm3. Microscopically, it is emerald-green, pleochroic from emerald-green (γ) to yellow-green (β) and greenish yellow (α). The new mineral is biaxial (+), γ = 2.15(1), β = 2.09(3), and α = 2.05(1), 2V meas = 80 ± (10)°, 2V calc = 80.5°. In reflected light, it is gray with green reflections; R max (589) = 12.9%; R min (589) = 12.3%, and there are strong, internal green reflections. The strongest absorption bands in the IR spectrum are as follows (cm?1): 935, 700, 614, 534. Space group Pnma, a = 9.727(3), b = 5.619(1), c = 4.499(1) Å, V = 245.9(3) Å3, Z = 4. The strongest reflections in the X-ray powder diffraction pattern are as follows (d Å, I, hkl): 4.08(40)(101), 3.31(90)(111), 2.629(50)(301), 2.434(50)(220), 2.381(40)(311), 2.139(60)(221), 1.651(100)(222). The average chemical composition of mariinskite (electron microprobe, wt %) is as follows: BeO 16.3, Al2O3 23.89, Cr2O3 58.67, Fe2O3 0.26, V2O3 0.26, TiO2 0.61, total is 99.98. The empirical formula, calculated on the basis of four O atoms is Be1.03(Cr1.22Al0.74Ti0.01Fe0.01V0.01)1.99O4. The compatibility index 1 ? (Kp/Kc), 0.019, is excellent. The type specimens are deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, and the Ural Geological Museum, Yekaterinburg, Russia.  相似文献   

11.
Luobusaite: A New Mineral   总被引:6,自引:0,他引:6  
A group of mantle minerals including about 70-80 subtypes of minerals are discovered from a podiform chromitite in Tibet, China. Recovered minerals include diamond, coesite, moissanite, wustite, Fe-silides and a new mineral, luobusaite. All of these minerals were hand-picked from heavymineral separates of the podiform chromitite in the mantle peridotite of an ophiolite. The grains of luobusaite are as host mineral with inclusions of native silicon or as an intergrowth with native silicon and Fe-Si phase. Luobusaite occurs as irregular grains, with 0.1-0.2 mm in size, consisting of very finegrained aggregates. The mineral is steel-grey in color, metallic luster, and opaque. The empirical formula (based on 2 for Si) is Fe0.83Si2, according to the chemical compositions of luobusaite. X-ray powder-diffraction data: orthorhombic system, space group Cmca, a = 9.874 (14) A, b = 7.784 (5) A, c= 7.829(7) A, Z=16.  相似文献   

12.
The new mineral species edgarite, FeNb3S6, was discovered in a feldspar-rich fenite, in a fenitized xenolith enclosed by nepheline syenite of the Khibina alkaline complex, Kola Peninsula, northwestern Russia. It occurs as platy inclusions (up to 0.15?mm) in Ti-(V)-rich pyrrhotite and ferroan alabandite, and as dark gray aggregates of platy grains located on the surface of the pyrrhotite. The associated minerals include Ti-(V)-rich marcasite, Mn-Fe-rich wurtzite-2H, corundum, nearly end member phlogopite, rutile, monazite-(Ce), and a graphite-like material. Edgarite is soft (VHN5;10= 135–205?kg/mm2), distinctly bireflectant, and has a strong anisotropy. Its reflectance in air (and in oil) (R1 and R2 in percent, respectively) is: 470?nm: 28.1, 40.2 (13.0, 24.2), 546?nm: 27.4, 39.3 (12.3, 22.7), 589?nm: 27.0, 38.5 (12.2, 21.7), and 650?nm: 27.0, 36.9 (12.4, 20.3). The composition is Nb 52.87, Fe 10.12, V 0.36, Mn 0.10, Ti 0.04, S 35.86, sum 99.35?wt%, which corresponds to (Fe0.96V0.04Mn0.01)Σ1.01Nb3.03S5.95 (basis: Σ atoms=10). By analogy with synthetic FeNb3S6, the X-ray powder pattern of edgarite was indexed on a hexagonal cell, a=5.771(1), c=12.190(6)?Å, and V=351.6(3)?Å3, D calc is 4.99?g/cm3. The space group is most probably P6322, with Z=2. The strongest lines of the pattern [d in Å (I, hkl)] are: 6.11 (8, 002), 3.04 (6, 004), 2.88 (5, 110), 2.606 (8, 112), 2.096 (10, 114), 1.665 (8, 300), 1.524 (6, 008), 1.126 (7, 322), and 1.027 (6, 414). Edgarite appears to have formed at a very late or final stage of metasomatism, after the main event of fenitization, from a highly reduced, subalkaline S-C-H-rich fluid, which may have remobilized Nb as a result of destabilization of oxide minerals. These reducing conditions promoted the chalcophile behavior of lithophile elements (Nb, Ti, V and Mn) on a local scale in the fenite.  相似文献   

13.
Wakefieldite‐(Nd), NdVO4, is a new mineral found from the Arase stratiform ferromanganese deposit in Kochi Prefecture, Shikoku Island, Japan. It is the Nd‐dominant analogue of wakefieldite‐(Y) and wakefieldite‐(Ce). The ferromanganese ore specimen mainly consists of hematite and caryopilite, and wakefieldite‐(Nd) is typically enclosed in caryopilite. Wakefieldite‐(Nd) is tetragonal, I41/amd, a = 7.338(16) Å, c = 6.509(19) Å, V = 350.5(18) Å3, Z = 4. The four strongest lines in the X‐ray diffraction pattern [d(Å), I/I0, hkl] using a Gandolfi camera are (3.67, 100, 200); (2.74, 51, 112); (4.84, 27, 101) and (1.89, 25, 312). Chemical composition of wakefieldite‐(Nd) are V2O3 35.25, As2O3 0.93, SiO2 0.14, MnO 1.45, Fe2O3 0.41, Y2O3 2.87, La2O3 7.61, Ce2O3 7.37, Pr2O3 6.04, Nd2O3 26.79, Sm2O3 4.41, Eu2O3 1.36, Gd2O3 3.41, Tb2O3 0.22, Dy2O3 1.41, Er2O3 0.10, total 99.77 wt.%. The empirical formula is (Nd0.403La0.118Ce0.114Pr0.093Y0.064Sm0.064Mn0.052Gd0.048Eu0.020Dy0.019Fe0.013Tb0.003Er0.001)1.012(V0.981As0.020Si0.006)1.007O4 on the basis of O = 4. The calculated density is 4.782 g/cm3. Microtexture and co‐existing relationship between wakefieldite‐(Nd) and caryopilite suggest that recrystallization and dehydration of Fe‐ and Mn‐oxyhydroxide led to the generation of hematite, caryopilite, rhodochrosite and wakefieldite‐(Nd) by the metamorphism during the accretion of the host unit of the Arase deposit. Chondrite‐normalized REE pattern of the host ferromanganese ore, which is regarded as oceanic metalliferous sediment in origin, shows negative Ce anomaly. Chemical composition of wakefieldite‐(Nd) reflects Ce‐depleted bulk composition of REE‐enriched ferromanganese ore.  相似文献   

14.
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), 2V meas = 50(10)°, 2V calc = 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(Fe 0.53 2+ Mn0.38Mg0.08)Σ0.99(Ti2.44Fe 0.80 3+ 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) ( $\overline 3 $ 11), 2.96 (100) ( $\overline 3 $ 13, 311), 2.80 (50) (020), 2.14 (50) ( $\overline 4 $ 22, $\overline 3 $ 15, 313), 1.947 (50) (024, 223), 1.657 (40) ( $\overline 4 $ 07, $\overline 4 $ 33, 331). The holotype specimen of perrierite-(La) is deposited at the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, Russia, with the registration number 4059/1.  相似文献   

15.
The new mineral sardignaite, a bismuth molybdate with formula BiMo2O7(OH)·2H2O, occurs in quartz veins within a granitic rock at Su Senargiu, near Sarroch, Sardegna, Italy. The name is after the locality. Sardignaite occurs a thin prismatic crystals up to 1 mm in length, with pale yellow color and a white streak. It is transparent with adamantine lustre, non fluorescent, and brittle with a conchoidal fracture. It is associated with bismuthinite, bismoclite, molybdenite, ferrimolybdite, koechlinite, wulfenite, and the new mineral IMA 2009–022. Mohs hardness is ca. 3. D calc is 4.82 g/cm3. The mineral is monoclinic, space group P21/m, with a 5.7797(7), b 11.567(1), c 6.3344(8) Å, β 113.360(9)°, V 388.8(1) Å3. The strongest lines in the powder X-ray diffraction pattern are d(I)(hkl): 3.206(100)(031), 5.03(80)(?101), 1.992(45)(221), 3.120(32)(130). The crystal structure of sardignaite was solved to R(F) 0.056 using single-crystal X-ray diffraction data, and is characterized by edge-sharing dimers of [MoO5(H2O)] octahedra, linked to each other through corner-sharing to give rise to corrugated columns running along b. Such columns are held together by Bi3+ cations, eight-fold coordinated by 7 O + 1 (OH). Both the mineral and its name were approved by the IMA-CNMNC.  相似文献   

16.
A new mineral romanorlovite has been found in the upper, moderately hot zones of two fumaroles, Glavnaya Tenoritovaya (Major Tenorite) and Arsenatnaya (Arsenate), located at the second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia. It is associated with avdoninite in both fumaroles, and in Glavnaya Tenoritovaya, it is also associated with belloite, sylvite, carnallite, mitscherlichite, sanguite, chlorothionite, eriochalcite, chrysothallite, and mellizinkalite. Romanorlovite occurs as prismatic, equant, or tabular tetragonal crystals up to 0.1 mm in size, crystal clusters up to 0.5 mm, and crusts up to 2 × 2 mm in area. The mineral is transparent with vitreous luster. Its color varies from yellow-brown to dark brown, and tiny crystals are honey- or golden-yellow. Cleavage is not observed. Romanorlovite is brittle. The Mohs hardness is ca ~3. The calculated density varies from 2.72 to 2.79 g/cm3 depending on the content of admixed Pb. The mineral is optically uniaxial (–), ω = 1.727(3), ε = 1.694(2). The Raman spectrum has been reported. The chemical composition of the holotype sample (wt %; electron microprobe data, contents of О and H calculated by stoichiometry) is as follows: 21.52 K, 0.89 Pb, 28.79 Cu, 0.02 Zn, 44.74 Cl, 4.85 Ocalc, 0.41 Hcalc, total 101.22. Its empirical formula calculated based on Cl25 with (ОН)4(Н2О)2 is K10.90Pb0.09Cu8.97Zn0.01Cl25(OH)4 · 2H2O. The simplified formula is K11Cu9Cl25(OH)4 · 2H2O (Z = 4). Romanorlovite is tetragonal, space group[ I4/mmm. The unit cell parameters are (1) holotype: a = 17.5804(7), c = 15.9075(6) Å, V = 4916.5(3) Å3; (2) the sample enriched in Pb on which the crystal structure was refined: a = 17.5538(19), c = 15.8620(17) Å, V= 4887.7(9) Å3. The strongest reflections of the powder XRD pattern (d, Å–I[hkl]) are 12.48–56[110], 11.74–36[101], 8.80–100[200], 7.97–34[002], 6.71–40[112], 3.165–32[512], 2.933–80[215, 433], 2.607–38[514]. The mineral is named in honor of Roman Yu. Orlov (1929-2005), Russian mineralogist and physicist, who worked in the Department of Mineralogy, Moscow State University.  相似文献   

17.
A new mineral of the neptunite group, magnesioneptunite KNa2Li(Mg,Fe)2Ti2Si8O24, a Mg-dominant analogue of neptunite and manganoneptunite, has been found in the Upper Chegem caldera near Mount Lakargi, Kabardino-Balkaria, the North Caucasus, Russia in a xenolith of altered sandstone located between skarnified carbonate xenoliths and ignimbrite. Magnesioneptunite occurs as nearly isometric grains and aggregates up to 0.1 mm in size in the cores of some grains of a Mg-rich variety of neptunite with Mg/(Fe + Mn) = 0.7?1.0. The chemical composition of magnesioneptunite with a maximum Mg content is as follows, wt %: 3.63 K2O, 8.21 Na2O, 1.73 Li2O, 6.47 MgO, 0.04 MnO, 5.87 FeO, 0.07 Al2O3, 18.73 TiO2, 56.88 SiO2, 99.62 in total. The empirical formula is (K0.67Na0.32Ca0.01)Σ1.00Na2.06Li1.00 · (Mg1.39Fe 0.71 2+ )Σ2.10(Si7.90Al0.01)Σ7.91O24. Grains of magnesioneptunite are dark brown to red-brown, translucent, with vitreous luster. D calc = 3.15 g/cm3, and the Mohs hardness is 5–6. Cleavage parallel to the (110) is perfect. The new mineral is optically biaxial, positive, α = 1.697(2), β = 1.708 (3), γ = 1.725(3), 2V meas = 45(15)°. The mineral is associated with quartz, alkali feldspar, rutile, aegirine, and neptunite. Magnesioneptunite and the Mg-rich variety of neptunite were formed as products of ilmenite alteration. Magnesioneptunite is monoclinic, C2/c; unit-cell parameters: a = 16.327(7), b = 12.4788(4), c = 9.9666(4) Å, β = 115.6519(5)°, V = 1830.5(1) Å3, Z = 4. The type specimen is deposited at the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow.  相似文献   

18.
The paper describes the first finding of quintinite [Mg4Al2(OH)12][(CO3)(H2O)3] at the Mariinsky deposit in the Central Urals, Russia. The mineral occurs as white tabular crystals in cavities within altered gabbro in association with prehnite, calcite, and a chlorite-group mineral. Quintinite is the probable result of late hydrothermal alteration of primary mafic and ultramafic rocks hosting emerald-bearing glimmerite. According to electron microprobe data, the Mg: Al ratio is ~2: 1. IR spectroscopy has revealed hydroxyl and carbonate groups and H2O molecules in the mineral. According to single crystal XRD data, quintinite is monoclinic, space group C2/m, a =5.233(1), b = 9.051(2), c = 7.711(2) Å, β = 103.09(3)°, V = 355.7(2) Å3. Based on structure refinement, the polytype of quintinite should be denoted as 1M. This is the third approved occurrence of quintinite-1M in the world after the Kovdor complex and Bazhenovsky chrysotile–asbestos deposit.  相似文献   

19.
The Mazaertag layered intrusion is located in the northwestern part of the Tarim large igneous province where several early Permian layered mafic-ultramafic intrusions host important Fe-Ti oxide deposits. The intrusion covers an area of ~0.13 km~2 and has a vertical stratigraphic thickness of at least300 m. It consists chiefly of olivine clinopyroxenite, and is cut through by the nearby mafic-ultramafic dykes. In this paper, we report new mineral chemistry data and whole-rock chemical and isotopic compositions for the Mazaertag intrusion along with whole-rock isotopic compositions for the nearby mafic dykes. The averaged compositions of cumulus olivine, clinopyroxene and intercumulus plagioclase within individual samples range from Fo_(71-73),Mg~# = 76 to 79 and An_(65-75) but they do not define sustained reversals. The observed mineral compositions are consistent with the differentiation of a single batch of magma in a closed system. Rocks of the Mazaertag intrusion are characterized by enrichment in light REE relative to heavy REE, positive Nb and Ta anomalies and a small range of age-corrected ε_(Nd)(t)(-0.1 to +0.9) and initial ~(87)Sr/~(86)Sr values(0.7044 to 0.7068). The slightly lower ε_(Nd)(t), initial ~(206)Pb/~(204)Pb and higher initial ~(87)Sr/~(86)Sr values of the intrusion compared to those of the least contaminated dykes[ε_(Nd)(t) =+2.8 to +3.4;(~(206)Pb/~(204)Pb)_i = 18.516-18.521;(~(87)Sr/~(86)Sr)_i = 0.7038-0.7041] imply that the Mazaertag magma was subjected to small to modest degrees of contamination by the upper crust. The Sr-Nd isotopic compositions of the least contaminated dykes are consistent with derivation from a FOZO-like mantle source. The parental magma of the Mazaertag intrusion, estimated from clinopyroxene compositions using mineral-melt partition coefficients, has trace element compositions similar to some of the most primitive mafic dykes in the same area. This suggests that the Mazaertag intrusion and mafic dykes shared a similar mantle source. Therefore, the parental magma of the Mazaertag intrusion was interpreted to have originated from a mantle plume. Based on the Cr_2 O_3 contents in titanomagnetite and less-evolved characteristics of the Mazaertag intrusion compared to the Wajilitag Fe-Ti oxide deposit in Bachu, it is speculated that there might not be a potential to find economic Fe-Ti oxide mineralization in the intrusion.  相似文献   

20.
Ertixiite (Na2Si4O9), a new mineral found in a miarolitic cavity of the Altay Pegmatite Mine, Xinjiang, China, is associated with topaz, apatite, quartz, cleavelandite, etc. The mineral is white, granular, and transparent. HNV=570.08?850.96 kg/mm2 (Moh’s 5.8?6.5), D=2.35, N=1.502. Cubic system,a=5.975 Å, V=213.311 Å, Z=1,D x =2.34g/cm3. The chemical composition of ertixiite (the average of six samples) is: Na2O 17.97, CaO 2.82, SiO2 77.86, Al2O3 1.45, FeO 0.05, total 100.15. The strongest lines in the X-ray powder pattern are 3.443(2, 111), 2.647(2. 210), 2.674(2,210), 1.996(8,221), 1.798(10,311), and 1.492(2,400).  相似文献   

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