Cesanite, Ca2Na3[(OH)(SO4)3] , a sulphate isotypic to apatite, from the Cesano geothermal field (Latium, Italy)

1981 ◽  
Vol 44 (335) ◽  
pp. 269-273 ◽  
Author(s):  
G. Cavarretta ◽  
A. Mottana ◽  
F. Tecce
Keyword(s):  
Geothermal Field ◽  
Coarse Grained ◽  
Theoretical Formula ◽  
Chemical Formula ◽  
Charge Balance ◽  
X Ray ◽  
Cell Parameters ◽  
Core Samples ◽  
Structural Identity ◽  
Cavity Filling

AbstractCesanite occurs both as a solid vein (1 cm thick) and as a cavity-filling of an explosive breccia in core samples of the Cesano 1 geothermal well (Cesano area, Latium, Italy).Cesanite is coloudess, medium to coarse grained, soft (H = 2 to 3) and light (ρmeas 2.786±0.002 g cm−3). It is uniaxial negative, ε = 1.564, ω = 1.570, with space group P63/m and cell parameters a = 9.442 (4), c = 6.903 (3) Å, for c/a = 0.730. Identifying spacings are 8.161, 2.822, 2.727,1.844 Å, in X-ray powder patterns strikingly similar to those of apatite. The chemical formula (microprobe analyses on two grains) is Ca1.53Sr0.03Na3.42K0.02[(Cl0.06F0.06OH0.44)(S2.99O12)]·0.44H2O, while the theoretical formula, derived from considerations on structural identity with apatite, is Ca2Na3[(OH)(SO4)3]. Cesanite is the end member of the apatite-wilkeite ellestadite series where [PO4]3− is entirely substituted by [SO4]2−, the charge balance being made up by Na+ substituting for Ca2+.

Structural analysis of excess-anion C-type rare earth oxide: a case study with Gd1−xCexO1.5+x/2(x= 0.20 and 0.40)

2003 ◽  
Vol 36 (4) ◽  
pp. 1082-1084 ◽  
Author(s):  
V. Grover ◽  
S. N. Achary ◽  
A. K. Tyagi
Keyword(s):  
Rare Earth ◽  
Structural Analysis ◽  
Metal Ion ◽  
Rare Earth Oxide ◽  
Charge Balance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Lattice Space

Structural analysis of anion-rich C-type Gd2O3was carried by the Rietveld refinement of the powder X-ray diffraction data for compositions Gd0.8Ce0.2O1.60and Gd0.6Ce0.4O1.70. Both compounds have a body-centred cubic lattice (space groupIa\bar{3}, No. 206,Z= 32) with unit-cell parameters of 10.8488 (1) and 10.8542 (1) Å, respectively. Both of these compounds are iso-structural with the C-type rare earth oxides, with excess anions as required for charge balance. The structural analysis reveals that there are two different kinds of metal ion site, namely 8b(M1) and 24d(M2), and two different kinds of anion sites, namely 48e(O1) and 16c(O2). The excess anions occupy the 16c(xxx) sites. The two metal ions each form an approximately eightfold-coordination polyhedron with O1 and O2. The details of these two compositions are explained and compared with both the CeO2structure and the Gd2O3structure,i.e.the end member.

scholarly journals Bohseit z beryl-columbitového pegmatitu D6e v Maršíkově (silezikum, Česká republika)

2020 ◽  
Vol 28 (1) ◽  
pp. 219-223 ◽  
Author(s):  
Zdeněk Dolníček ◽  
Miroslav Nepejchal ◽  
Jiří Sejkora ◽  
Jana Ulmanová ◽  
Štěpán Chládek
Keyword(s):  
Compositional Data ◽  
Coarse Grained ◽  
Powder Diffraction Data ◽  
Unit Cell Parameters ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Pegmatite Body ◽  
Small Crystals ◽  
Hydrothermal Stage

Bohseite was found in a lenticular body of D6e beryl-columbite granitic pegmatite near Maršíkov, which is hosted by amphibole gneisses of the Sobotín Amphibolite Massif (Silesicum, northeastern part of Czech Republic). Bohseite forms chalky white aggregates up to 1 cm in size, which are hosted by small vugs in the coarse-grained pegmatite. It is associated with small crystals of quartz, adularia, albite, muscovite and epidote. Bohseite is orthorhombic, space group Cmcm with following unit-cell parameters refined from X-ray powder diffraction data: a 23.210(2), b 4.955(2), c 19.428(3) Å and V 2234.5(1.0) Å3. The electron microprobe compositional data of bohseite are presented. Bohseite from Maršíkov contains 14.3 - 42.5 mol. % of bavenite component, up to 0.06 apfu Na and 0.13 - 0.36 apfu F. The association with other beryllium-rich phases (milarite, bertrandite) points to variable activities of Be and Al during hydrothermal stage of evolution of the pegmatite body. The likely source of Be was beryl, which is sometimes completely dissolved and vugs after its crystals are lined by small crystals of above mentioned hydrothermal phases.

The mineralogy of the historical Mochalin Log REE deposit, South Urals, Russia. Part II. Radekškodaite-(La), (CaLa5)(Al4Fe2+)[Si2O7][SiO4]5O(OH)3 and radekškodaite-(Ce), (CaCe5)(Al4Fe2+)[Si2O7][SiO4]5O(OH)3, two new minerals with a novel structure-type belonging to the epidote–törnebohmite polysomatic series

2020 ◽  
pp. 1-15
Author(s):  
Anatoly V. Kasatkin ◽  
Natalia V. Zubkova ◽  
Igor V. Pekov ◽  
Nikita V. Chukanov ◽  
Dmitriy A. Ksenofontov ◽  
...  
Keyword(s):  
Czech Republic ◽  
Structure Type ◽  
Associate Professor ◽  
South Urals ◽  
Charge Balance ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Novel Structure

Abstract Two new isostructural minerals radekškodaite-(La) (CaLa5)(Al4Fe2+)[Si2O7][SiO4]5O(OH)3 and radekškodaite-(Ce) (CaCe5)(Al4Fe2+)[Si2O7][SiO4]5O(OH)3 were discovered in polymineralic nodules from the Mochalin Log REE deposit, South Urals, Russia. Radekškodaite-(La) is associated with allanite-(Ce), allanite-(La), bastnäsite-(Ce), bastnäsite-(La), ferriallanite-(Ce), ferriallanite-(La), ferriperbøeite-(La), fluorbritholite-(Ce), törnebohmite-(Ce) and törnebohmite-(La). Radekškodaite-(Ce) is associated with ancylite-(Ce), bastnäsite-(Ce), bastnäsite-(La), lanthanite-(La), perbøeite-(Ce) and törnebohmite-(Ce). The new minerals form isolated anhedral grains up to 0.35 × 0.75 mm [radekškodaite-(La)] and 1 mm × 2 mm [radekškodaite-(Ce)]. Both minerals are greenish-brown with vitreous lustre. Dcalc = 4.644 [radekškodaite-(La)] and 4.651 [radekškodaite-(Ce)] g cm–3. Both minerals are optically biaxial (+); radekškodaite-(La): α = 1.790(7), β = 1.798(5), γ = 1.825(8) and 2Vmeas = 60(10)°; radekškodaite-(Ce): α = 1.798(6), β = 1.806(6), γ = 1.833(8) and 2Vmeas = 65(10)°. Chemical data [wt.%, electron-microprobe; FeO:Fe2O3 by charge balance; H2O by stochiometry; radekškodaite-(La)/radekškodaite-(Ce)] are: CaO 3.40/2.74, La2O3 27.68/22.23, Ce2O3 20.39/24.30, Pr2O3 0.94/1.48, Nd2O3 1.71/3.18, ThO2 0.23/0.24, MgO 0.85/1.04, Al2O3 10.35/10.84, MnO 0.64/0.69, FeO 2.55/2.76, Fe2O3 3.12/2.57, TiO2 0.13/0.04, SiO2 26.03/26.10, F 0.10/0.09, H2O 1.62/1.63, –O=F –0.04/–0.04, total 99.70/99.89. The empirical formulae based on O28(OH,F)3 are: radekškodaite-(La): (Ca0.98Th0.01La2.75Ce2.01Nd0.16Pr0.09)Σ6.00(Al3.28Fe3+0.63Fe2+0.57Mg0.34Mn0.15Ti0.03)Σ5.00Si7.00O28[(OH)2.91F0.09]; radekškodaite-(Ce): (Ca0.79Mn0.16Th0.01Ce2.39La2.20Nd0.30Pr0.14)Σ5.99(Al3.43Fe2+0.62Fe3+0.52Mg0.42Ti0.01)Σ5.00Si7.00O28[(OH)2.92F0.08]. Both minerals are monoclinic, P21/m; the unit-cell parameters [radekškodaite-(La)/radekškodaite-(Ce)] are: a = 8.9604(3)/8.9702(4), b = 5.7268(2)/5.7044(2), c = 25.1128(10)/25.1642(13) Å, β = 116.627(5)/116.766(6)°, V = 1151.98(7)/1149.68(11) Å3 and Z = 2/2. The crystal structures are solved based on single-crystal X-ray diffraction data; R = 0.0554 [radekškodaite-(La)] and 0.0769 [radekškodaite-(Ce)]. Both minerals belong to the epidote–törnebohmite polysomatic series and represent first members of ET2-type: their structure consists of regular alternating modules, one slab of the epidote (E) structure and two slabs of törnebohmite (T). The rootname radekškodaite is given in honor of the Czech mineralogist Radek Škoda (born 1979), Associate Professor at Masaryk University, Brno, Czech Republic. The suffix-modifier -(La) or -(Ce) indicates the predominance of La or Ce among REE in the mineral.

X-ray diffraction data of 4-phenyl-6-(trifluoromethyl)-3,4-dihydroquinolin-2(1H)-one and its synthetic precursor N-[4-(trifluoromethyl)phenyl]cinnamamide

2016 ◽  
Vol 31 (3) ◽  
pp. 233-239
Author(s):  
Jose H. Quintana Mendoza ◽  
J. A. Henao ◽  
Carlos E. Rondón Flórez ◽  
Carlos E. Puerto Galvis ◽  
Vladimir V. Kouznetsov
Keyword(s):  
Cell Volume ◽  
Title Compound ◽  
Unit Cell Volume ◽  
Unit Cell ◽  
Chemical Formula ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Parameters

The title compound, the 4-phenyl-6-(trifluoromethyl)-3,4-dihydroquinolin-2(1H)-one (4) with chemical formula: (C16H12F3NO), was synthesized from N-[4-(trifluoromethyl)phenyl]cinnamamide (3), chemical formula: (C16H12F3NO), through an intramolecular cyclization mediated by triflic acid. Preliminary molecular characterization of both compounds was performed by Fourier transform infrared spectroscopy, gas chromatography mass spectrometry, and nuclear magnetic resonance spectroscopy (1H, 13C); crystallographic characterization was completed by X-ray diffraction of polycrystalline samples. The title compound 4 crystallized in a monoclinic system and unit-cell parameters are reported [a = 16.002 (3), b = 5.170 (1), c = 17.733 (3) Å, β = 111.11 (2)°, unit-cell volume V = 1368.5 (3) Å3, Z = 4] P21/c (No. 14) space group; the title compound 3 crystallized in a monoclinic system and unit-cell parameters are reported [a = 12.902 (2), b = 5.144 (1), c = 20.513 (5) Å, β = 91.67 (2)°, unit-cell volume V = 1360.7 (4) Å3, Z = 4] P21/c (No. 14) space group.

Schmidite and wildenauerite, two new schoonerite-group minerals from the Hagendorf-Süd pegmatite, Oberpfalz, Bavaria

2018 ◽  
Vol 83 (02) ◽  
pp. 181-190
Author(s):  
Ian E. Grey ◽  
Erich Keck ◽  
Anthony R. Kampf ◽  
John D. Cashion ◽  
Colin M. MacRae ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Tetrahedral Site ◽  
Orthorhombic Symmetry ◽  
Charge Balance ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Symmetry Space ◽  
Symmetry Space Group

AbstractSchmidite, Zn(Fe3+0.5Mn2+0.5)2ZnFe3+(PO4)3(OH)3(H2O)8 and wildenauerite, Zn(Fe3+0.5Mn2+0.5)2Mn2+Fe3+(PO4)3(OH)3(H2O)8 are two new oxidised schoonerite-group minerals from the Hagendorf-Süd pegmatite, Hagendorf, Oberpfalz, Bavaria, Germany. Schmidite occurs as radiating sprays of orange–brown to copper-red laths on and near to altered phosphophyllite in a corroded triphylite nodule, whereas wildenauerite forms dense compacts of red laths, terminating Zn-bearing rockbridgeite. The minerals are biaxial (+) with α = 1.642(2), β = 1.680(1), γ = 1.735(2) and 2Vmeas = 81.4(8)° for schmidite, and with α = 1.659(3), β = 1.687(3), γ = 1.742(3) and 2Vmeas = 73(1)° for wildenauerite. Electron microprobe analyses, with H2O from thermal analysis and FeO/Fe2O3 from Mössbauer spectroscopy, gave FeO 0.4, MgO 0.3, Fe2O3 23.5, MnO 9.0, ZnO 15.5, P2O5 27.6, H2O 23.3, total 99.6 wt.% for schmidite, and FeO 0.7, MgO 0.3, Fe2O3 25.2, MnO 10.7, ZnO 11.5, P2O5 27.2, H2O 24.5, total 100.1 wt.% for wildenauerite. The empirical formulae, scaled to 3 P and with OH– adjusted for charge balance are Zn1.47Mn2+0.98Mg0.05Fe2+0.04Fe3+2.27(PO4)3(OH)2.89(H2O)8.54 for schmidite and Zn1.11Mn2+1.18Mg0.05Fe2+0.08Fe3+2.47(PO4)3(OH)3.25(H2O)9.03 for wildenauerite. The two minerals have orthorhombic symmetry, space group Pmab and Z = 4. The unit-cell parameters from refinement of powder X-ray diffraction data are a = 11.059(1), b = 25.452(1) and c = 6.427(1) Å for schmidite, and a = 11.082(1), b = 25.498(2) and c = 6.436(1) Å for wildenauerite. The crystal structures of schmidite and wildenauerite differ from that of schoonerite in having minor partitioning of Zn from the [5]Zn site to an adjacent vacant tetrahedral site [4]Zn, separated by ~1.0 Å from [5]Zn. The two minerals are distinguished by the cation occupancies in the octahedral M1 to M3 sites. Schmidite has M1 = M2 = (Fe3+0.5Mn2+0.5) and M3 = Zn and wildenauerite has M1 = M2 = (Fe3+0.5Mn2+0.5) and M3 = Mn2+.

Tavagnascoite, Bi4O4(SO4)(OH)2, a new oxyhydroxy bismuth sulfate related to klebelsbergite

2016 ◽  
Vol 80 (4) ◽  
pp. 647-657 ◽  
Author(s):  
Luca Bindi ◽  
Cristian Biagioni ◽  
Bruno Martini ◽  
Adrio Salvetti ◽  
Giovanni Dalla Fontana ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
New Mineral ◽  
Chemical Formula ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Rounding Errors ◽  
X Ray ◽  
Cell Parameters ◽  
Ore District

AbstractThe new mineral tavagnascoite, Bi4O4(SO4)(OH)2, was discovered in the Pb-Bi-Zn-As-Fe-Cu ore district of Tavagnasco, Turin, Piedmont, Italy. It occurs as blocky, colourless crystals, up to 40 μm in size, with a silky lustre. In the specimen studied, tavagnascoite is associated with other uncharacterized secondary Bi-minerals originating from the alteration of a bismuthinite ± Bi-sulfosalt assemblage. Electron microprobe analyses gave (average of three spot analyses, wt.%) Bi2O385.32, Sb2O30.58, PbO 2.18, SO38.46, H2Ocalc1.77, sum 98.31. On the basis of 10 O apfu, the chemical formula is (Bi3.74Pb0.10Sb0.04)∑ = 3.88O3.68(SO4)1.08(OH)2, with rounding errors. Main calculated diffraction lines are [din Å (relative intensity)hkl] 6.39 (29) 012, 4.95 (19) 111,4.019(32)121,3.604(28)014 and 3.213(100)123. Unit-cell parameters area= 5.831(1),b= 11.925(2),c= 15.123(1) Å,V= 1051.6(3) Å3, Z = 4, space groupPca21. The crystal structure was solved and refined from single-crystal X-ray diffraction data toR1= 0.037 on the basis of 1269 observed reflections. It consists of Bi–O polyhedra and SO4tetrahedra. Bismuth polyhedra are connected each to other to form Bi–O sheets parallel to (001). Successive sheets are linked together by SO4groups and hydrogen bonds. Tavagnascoite is the Bi-analogue of klebelsbergite, Sb4O4(SO4)(OH)2, and it is the fifth natural known bismuth sulfate without additional cations. The mineral and its name have been approved by the IMA CNMNC (2014-099).

Armstrongite from the Strange Lake Alkalic Complex, on the Quebec – Labrador Boundary, Canada

1987 ◽  
Vol 2 (1) ◽  
pp. 2-4 ◽  
Author(s):  
John L. Jambor ◽  
Andrew C. Roberts ◽  
Joel D. Grice
Keyword(s):  
Electron Microprobe ◽  
Unit Cell ◽  
Powder Pattern ◽  
Theoretical Formula ◽  
Monoclinic Space Group ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
No Absorption

AbstractTabular untwinned crystals of colorless transparent armstrongite from the Strange Lake Alkalic Complex, on the Quebec – Labrador boundary, Canada are monoclinic, space group choices I2/m, I2, Im (diffraction aspect I*/*), with refined unit-cell parameters a = 13.599 (9), b = 14.114(9), c = 7.833 (4) Å, β = 103.41 (5)°, V = 1462.4 (±3.0) Å3. a:b:c = 0.9635:1:0.5550, Z = 4 and D(x) = 2.696 g/cm3. A fully indexed X-ray powder pattern is presented. Averaged electron-microprobe analyses suggest a theoretical formula of CaZrSi6O15 · 3 H2O. The Strange Lake armstrongite is biaxial negative, α = 1.567 (1), β = 1.576 (1), γ = 1.577 (1), 2V (meas.) = 39 (1)°, 2V (calc.) = 37°, Z∥b, X Λc = +4°, with no absorption and weak dispersion r < v.

scholarly journals INCORPORATION OF Mo6+ IN FERRIHYDRITE, GOETHITE, AND HEMATITE

2021 ◽  
Author(s):  
Marcel G. Görn ◽  
Ralph M. Bolanz ◽  
Stephen Parry ◽  
Jörg Göttlicher ◽  
Ralph Steininger ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Structural Disorder ◽  
Unit Cell ◽  
Emission Spectrometry ◽  
Charge Balance ◽  
Unit Cell Parameters ◽  
Edge Structure ◽  
X Ray ◽  
Cell Parameters ◽  
X Ray Absorption

AbstractAmong all iron oxides, hematite (α-Fe2O3), goethite (α-FeOOH), and ferrihydrite (FeOOH⋅nH2O) are the most common mineral species. While immobilization of Mo6+ by surface adsorption on ferric oxides has been studied extensively, the mechanisms of incorporation in their structure have been researched little. The objective of this study was to investigate the relation between Mo content and its structural incorporation in hematite, goethite, and six-line ferrihydrite by a combination of X-ray absorption spectroscopy (XAS), powder X-ray diffraction (pXRD), and inductively-coupled plasma optical emission spectrometry (ICP-OES). Synthesized in the presence of Mo, the hematite, goethite, and six-line ferrihydrite phases incorporated up to 8.52, 0.03, and 17.49 wt. % Mo, respectively. For hematite and goethite, pXRD analyses did not indicate the presence of separate Mo phases. Refined unit-cell parameters correlated with increasing Mo concentration in hematite and goethite. The unit-cell parameters indicated an increase in structural disorder within both phases and, therefore, supported the structural incorporation of Mo in hematite and goethite. Analysis of pXRD measurements of Mo-bearing six-line ferrihydrites revealed small amounts of coprecipitated akaganéite. X-ray absorption near edge structure (XANES) measurements at the Mo L3-edge indicated a strong distortion of the MoO6 octahedra in all three phases. Fitting of extended X-ray absorption fine structure (EXAFS) spectra of the Mo K-edge supported the presence of such distorted octahedra in a coordination environment similar to the Fe position in the investigated specimen. Incorporation of Mo6+ at the Fe3+-position for both hematite and goethite resulted in the formation of one Fe vacancy in close proximity to the newly incorporated Mo6+ and, therefore, charge balance within the hematite and goethite structures.

Synthesis and X-ray diffraction data of 6,8-dimethyl-cis-2-vinyl-2,3,4,5-tetrahydro-1H-benzo[b]azepin-4-ol and 8-chloro-9-methyl-cis-2-(prop-1-en-2-yl)-2,3,4,5-tetrahydro-1H-benzo[b]azepin-4-ol

2011 ◽  
Vol 26 (4) ◽  
pp. 346-349 ◽  
Author(s):  
M. A. Macías ◽  
J. A. Henao ◽  
Lina María Acosta ◽  
Alirio Palma
Keyword(s):  
Unit Cell ◽  
Chemical Formula ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Monoclinic System ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Patterns ◽  
New Compounds

The 6,8-dimethyl-cis-2-vinyl-2,3,4,5-tetrahydro-1H-benzo[b]azepin-4-ol (2a) (Chemical formula C14H19NO) and 8-chloro-9-methyl-cis-2-(prop-1-en-2-yl)-2,3,4,5-tetrahydro-1H-benzo[b]azepin-4-ol (2b) (Chemical formula C14H18ClNO) were prepared via the reductive cleavage of the bridged N-O bond of the corresponding 1,4-epoxytetrahydro-1-benzazepines. The X-ray powder diffraction patterns for the new compounds were obtained. The compound 2a was found to crystallize in an orthorhombic system with space group Pmn21 (No. 31), refined unit-cell parameters a = 19.422(6) Å, b = 6.512(3) Å, c = 9.757(4) Å and V = 1234.0(5) Å3. The compound 2b was found to crystallize in a monoclinic system with space group P21/m (No. 11), refined unit-cell parameters a = 17.570(4) Å, b = 8.952(3) Å, c = 14.985(4) Å, β = 101.66(2)°, and V = 2308.3(9) Å3.

scholarly journals Mineralogie křemenných žil ložiska cínových rud Hřebečná u Abertam v Krušných horách (Česká republika)

2021 ◽  
Vol 29 (1) ◽  
pp. 131-163
Author(s):  
Jiří Sejkora ◽  
Petr Pauliš ◽  
Michal Urban ◽  
Zdeněk Dolníček ◽  
Jana Ulmanová ◽  
...  
Keyword(s):  
Coarse Grained ◽  
Powder Diffraction Data ◽  
Vein Quartz ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Fine Grained ◽  
Mineral Phases ◽  
Supergene Processes ◽  
Krušné Hory Mountains

An extraordinary rich mineral assemblage (more than 35 determined mineral species) has been discovered in quartz greisen mineralization found at dump material of the abandoned Mauritius mine. This mine is situated about 1 km N of the Hřebečná village, 16 km N of Karlovy Vary, Krušné hory Mountains, Czech Republic. The studied mineralization with its textural and mineralogical character differs significantly from the usual fine-grained greisens mined in this area. The primary mineralization is represented by coarse-grained quartz and fluorapatite with sporadic zircon, monazite-(Ce), xenotime-(Y) and very rare cassiterite. Besides common sulphides (arsenopyrite, chalcopyrite, pyrite, sphalerite, tetrahedrite-group minerals), Bi-sulphosalts (aikinite, bismuthinite, berryite, cuprobismutite, emplectite, wittichenite) were determined. Members of the tetrahedrite group also contain increased amounts of Bi - in addition to Bi-rich tennantite-(Zn) and tennantite-(Fe), microscopic zones represented by the not approved Bi-dominant analogue of tennantite („annivite-(Zn)“) were also found. The primary mineralization was intensively affected by supergene processes. Chalcopyrite and sphalerite are replaced by Cu sulphides - especially anilite and digenite, and more rarely by geerite, spionkopite and covellite. Some of the fluorapatite grains in the vein quartz were decomposed and mrázekite, mixite, libethenite, pseudomalachite, hydroxylpyromorphite, metatorbernite as well as rare dzhalindite crystallized in the resulting cavities. However, the most abundant supergene phases are the minerals of the alunite supergroup - crandallite, goyazite, plumbogummite, svanbergite and waylandite. The detailed descriptions, X-ray powder diffraction data, refined unit-cell parameters and quantitative chemical composition of individual studied mineral phases are presented.

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