On pink epsomites and fauserite

In 1865 A. Breithaupt described a new mineral from Herrengrund, Hungary, to which he gave the name of fauserite. It formed very pale pink crystalline aggregates and prismatic crystals, with prism angle near 88°42′ (over a), apparently orthorhombic, and cleavage b(010). Two other prisms with angles (over a) 54°39′ and 107° 50′ were observed, and a pyramid p, giving mp= 52° ; these would correspond to forms (210), (340), and (111), and the angles are near those of epsomite. An analysis by Mollnár gave the figures shown under I below—a magnesium and manganese sulphate hexahydrate, with the molecular ratio MgSO4(Mn,Mg)SO4 = 31.62 %. There is no evidence that the analysed material (stated to be crystalline) was homogeneous.

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Juansilvaite, Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, a new arsenate-sulfate from the Torrecillas mine, Iquique Province, Chile

Mineralogical Magazine ◽

10.1180/minmag.2016.080.113 ◽

2017 ◽

Vol 81 (3) ◽

pp. 619-628 ◽

Cited By ~ 1

Author(s):

Anthony R. Kampf ◽

Barbara P. Nash ◽

Maurizio Dini ◽

Arturo A. Molina Donoso

Keyword(s):

Obtuse Angle ◽

New Mineral ◽

X Ray Diffraction ◽

Calculated Density ◽

Sodium Cations ◽

Pale Pink ◽

Bright Pink ◽

Interlayer Region ◽

Mohs Hardness ◽

Irregular Cleavage

AbstractThe new mineral juansilvaite (IMA2015-080), Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, was foOptically, juansilvaiteund at the Torrecillas mine, Iquique Province, Chile, where it occurs as asecondary alteration phase in association with anhydrite, canutite, halite, sulfur and a mahnertite-like phase. Juansilvaite occurs as bright pink blades up to ∼0.5 mm long grouped in tightly intergrown radial aggregates and also as opaque dull pale pink rounded aggregates. Blades areflattened on {001}, elongated on [100] and exhibit the forms {001}, {111} and {201}. Crystals are transparent, with vitreous lustre and white streak. The Mohs hardness is ∼2½, tenacity is brittle and fracture is irregular. Cleavage is very good on {001}. The measured density is3.01(2) g cm–3 and the calculated density is 3.005 g cm–3. Optically, juansilvaite is biaxial (+) with α= 1.575(1), β = 1.597(1), γ= 1.623(1) and 2V = 86(1)° (measured in white light). Dispersion is r < v, slight, andthe orientation is X = b; Z ^ c = 27° in the obtuse angle β. The pleochroism is X > Y ≈ Z in shades of pale pink. The mineral is slowly soluble in dilute HCl at room temperature. The empirical formula, determined from electron-microprobeanalyses, is Na4.95Al2.28Fe0.503+Mn0.213+Cu0.04As5.92S1.83O36H17.37. Juansilvaite is monoclinic, C2/c, a = 18.1775(13), b = 8.6285(5), c= 18.5138(13) Å, β = 90.389(6)°, V = 2903.7(3) Å3 and Z = 4. The eight strongest powder X-ray diffraction lines are [dobs Å(I)(hkl)]: 9.25(100)(002), 7.20(34)(111), 4.545(34)(400), 3.988(39)(114), 3.363(42)(314), 3.145(66)(512,420), 2.960(68)(422,422) and 2,804(33)(131,423). The structure of juansilvaite (R1 = 3.82% for 2040 Fo > 4σF reflections) contains layers made up of alternating corner-linked Al–O octahedra and acid-arsenate tetrahedra. Sodium cations occur both peripheral to the layers and within cavities in the layers. An SO4 tetrahedron and an H2O group also are in the interlayer region.

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Magnesiokoritnigite, Mg(AsO3OH)·H2O, from the Torrecillas mine, Iquique Province, Chile: the Mg-analogue of koritnigite

Mineralogical Magazine ◽

10.1180/minmag.2013.077.8.03 ◽

2013 ◽

Vol 77 (8) ◽

pp. 3081-3092 ◽

Cited By ~ 6

Author(s):

A. R. Kampf ◽

B. P. Nash ◽

M. Dini ◽

A. A. Molina Donoso

Keyword(s):

Powder Diffraction ◽

Electron Microprobe ◽

New Mineral ◽

Optical Orientation ◽

Secondary Alteration ◽

X Ray ◽

Conchoidal Fracture ◽

Pale Pink ◽

Perfect Cleavage ◽

Mohs Hardness

AbstractThe new mineral magnesiokoritnigite (IMA 2013-049), ideally Mg(AsO3OH)·H2O, was found at the Torrecillas mine, Salar Grande, Iquique Province, Chile, where it occurs as a secondary alteration phase in association with anhydrite, chudobaite, halite, lavendulan, quartz and scorodite. Crystals of magnesiokoritnigite are colourless to pale-pink, thin to thick laths up to 2 mm long. Laths are elongated on [001], flattened on {010} and exhibit the forms {010}, {110}, {10}, {101}, {031} and {01}. The crystals also occur in dense deep-pink intergrowths. Crystals are transparent with a vitreous lustre. The mineral has a white streak, Mohs hardness of ∼3, brittle tenacity, conchoidal fracture and one perfect cleavage on {101}. The measured and calculated densities are 2.95(3) and 2.935 g cm– 3, respectively. Optically, magnesiokoritnigite is biaxial (+) with α = 1.579(1), β = 1.586(1) and γ = 1.620(1) (measured in white light). The measured 2V is 50(2)° and the calculated 2V is 50°. Dispersion is r < v, medium. The optical orientation is Y ≈ b; Z ^ c = 36° in obtuse β (note pseudomonoclinic symmetry). The mineral is non-pleochroic. The empirical formula, determined from electron-microprobe analyses, is (Mg0.94Cu0.03Mn0.02Ca0.01)Σ 1.00As0.96O5H3.19. Magnesiokoritnigite is triclinic, P, with a = 7.8702(7), b = 15.8081(6), c = 6.6389(14) Å, α = 90.814(6), β = 96.193(6), γ = 90.094(7)°, V = 821.06(19) Å3 and Z = 8. The eight strongest X-ray powder diffraction lines are [dobs Å (I)(hkl)]: 7.96(100)(020), 4.80(54)(101), 3.791(85)(10,210,1,31), 3.242(56)(02,1,012), 3.157(92)(21,30,230), 3.021(61)(11,141,21,221), 2.798(41)(02,032) and 1.908(43)(multiple). The structure, refined to R1 = 5.74% for 2360 Fo > 4σF reflections, shows magnesiokoritnigite to be isostructural with koritnigite and cobaltkoritnigite.

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Parkinsonite, (Pb,Mo, □)8O8Cl2, a new mineral from Merehead Quarry, Somerset

Mineralogical Magazine ◽

10.1180/minmag.1994.058.390.06 ◽

1994 ◽

Vol 58 (390) ◽

pp. 59-68 ◽

Cited By ~ 11

Author(s):

R. F. Symes ◽

G. Cressey ◽

A. J. Griddle ◽

C. J. Stanley ◽

J. G. Francis ◽

...

Keyword(s):

Refractive Indices ◽

New Mineral ◽

Synthetic Material ◽

Synthetic Sample ◽

Calculated Density ◽

X Ray ◽

Usual Form ◽

A Cell ◽

The Difference ◽

Crystalline Aggregates

AbstractParkinsonite, ideally (Pb,Mo,□)8O8Cl2, is a new mineral from the Merehead Quarry, Cranmore, Somerset, England. It occurs as compact clusters or patches of red to purplish red bladed crystals, which have an adamantine lustre and a perfect {001} cleavage and occupy fractures and cavities in carbonate vughs in veins of manganese and iron oxide and hydroxide minerals. Associated minerals are mendipite, diaboleite, chloroxiphite, wulfenite, cerussite and hydrocerussite. Discrete crystals were not found; intergrown crystalline aggregates are the usual form of occurrence. The maximum grain size is about 300 × 100 µm, but most grains are appreciably smaller. Parkinsonite was synthesized using high purity chemicals. The measured density of the synthetic material is 7.32 g/cm3; the calculated density is 7.39 g/cm3, the difference being due to minor impurity and slight porosity in the synthetic sample. Parkinsonite is translucent. Reflectance spectra were obtained in air and in oil. Refractive indices calculated from these (at 589 nm) are for Ro, 2.58, and Re', 2.42, i.e. uniaxial negative. VHN50 is 113–133 from which the calculated Mobs hardness is 2–2.5.X-ray studies show that parkinsonite is tetragonal with space group I4/mmm, I4̄2m, I4̄m2, I4/mm, or I422 and a 3.9922(3), c 22.514(2) Å. It has a cell volume of 358.82(5) Å3 with Z = 1. The strongest six lines of the X-ray powder diffraction pattern are [d in Å (I) (hkl)] 2.823, 2.813(100) (110,008); 5.63(85) (004); 2.251(33) (116, 0.0.10); 2.988(27) (105); 3.750(15) (006); 1.994(11) (200,118). Averaged electron microprobe analyses give the empirical formula Pb6.34Mo0.89□0.77O8.02Cl1.98 on the basis of 10 atoms [O + Cl]. The name is for Reginald F. D. Parkinson, mineral collector of Somerset, UK, who first found the mineral.

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Cannonite, Bi2O(OH)2SO4, a new mineral from Marysvale, Utah, USA

Mineralogical Magazine ◽

10.1180/minmag.1992.056.385.17 ◽

1992 ◽

Vol 56 (385) ◽

pp. 605-609 ◽

Cited By ~ 9

Author(s):

C. J. Stanley ◽

A. C. Roberts ◽

D. C. Harris ◽

A. J. Criddle ◽

J. T. Szymañski

Keyword(s):

United States Of America ◽

Refractive Indices ◽

New Mineral ◽

Mining District ◽

X Ray ◽

Conchoidal Fracture ◽

Reflected Light ◽

A Cell ◽

Mohs Hardness ◽

Crystalline Aggregates

AbstractCannonite, ideally Bi2O(OH)2SO4, is a new mineral from the Tunnel Extension mine, Ohio Mining District, Marysvale, Utah, USA. It occurs mostly as intergrown crystalline aggregates (<1 mm) of subhedral to euhedral equant to prismatic crystals (<200 μm) in cavities in quartz gangue. Other associated minerals are cuprobismutite, bismuthinite, and covelline. Cannonite is colourless and transparent with an adamantine lustre and white streak. It is brittle with an uneven to conchoidal fracture. In reflected light it is low reflecting, weakly to moderately bireflectant and weakly anisotropic. Internal reflections (colourless to white) are abundant. Measured reflectance values in air and oil are tabulated. Colour values relative to the CIE illuminant C for R1 and R2 in air respectively are: Y% 10.4, 11.7; Lambdad 475,475; Pe% 2.6, 3.0. Calculated refractive indices at 589 nm: R1 1.91 and R2 1.99. VHN100 229 (range 183-280); calculated Mohs hardness is 4.X-ray studies show that cannonite is monoclinic with space group P21/c and a 7.700(3), b 13.839(6), c 5.686(2) Å, β 109.11(3) ° It has a cell volume of 572.5(4) Å3 with Z = 4. Dcalc. is 6.515 g/cm3. The strongest six lines of the X-ray powder pattern are [d in Å (I) (hkl)] 3.206 (100) (221); 1.984 (90) (340, 152); 2.924 (70) (131); 3.644 (60) (111); 3.466 (60) (040); 2.782 (50) (112). Averaged probe analyses gave the empirical formula Bi1.99O(OH1.04)2S0.99O4 on the basis of 7 oxygen atoms. The name is for Benjamin Bartlett Cannon of Seattle, Washington, United States of America.

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Geschieberite, K2(UO2)(SO4)2(H2O)2, a new uranyl sulfate mineral from Jáchymov

Mineralogical Magazine ◽

10.1180/minmag.2015.079.1.16 ◽

2015 ◽

Vol 79 (1) ◽

pp. 205-216 ◽

Cited By ~ 6

Author(s):

J. Plášil ◽

J. Hloušek ◽

A. V. Kasatkin ◽

R. Škoda ◽

M. Novák ◽

...

Keyword(s):

Pentagonal Bipyramid ◽

New Mineral ◽

X Ray Diffraction ◽

Uranyl Sulfate ◽

Calculated Density ◽

Perfect Cleavage ◽

Mohs Hardness ◽

Bright Green ◽

Stretching Vibrations ◽

Crystalline Aggregates

AbstractThe new mineral geschieberite (IMA2014-006), K2(UO2)(SO4)2(H2O)2, was found in the Svornost mine, Jáchymov, Czech Republic, where it occurs as a secondary alteration phase after uraninite in association with adolfpateraite and gypsum. Geschieberite forms crystalline aggregates of bright green colour (when thick) composed of multiply intergrown prismatic crystals elongated on [001] typically reaching 0.1–0.2 mm across; observable forms are {010} and {001}. Crystals are translucent to transparent with a vitreous lustre. The mineral is brittle, with perfect cleavage on {100} and an uneven fracture. It has a greenish-white streak and a probable Mohs hardness of ∼2. The mineral is slightly soluble in cold H2O. The calculated density is 3.259 g cm–3. The mineral exhibits strong yellowish-green fluorescence under both shortwave and longwave UV radiation. Optically, geschieberite is biaxial (–), with β = 1.596(2) and γ = 1.634(4) (measured at 590 nm), with X = a. Electron-microprobe analyses provided Na2O 0.23, K2O 14.29, MgO 2.05, CaO 0.06, UO3 49.51, SO3 27.74, H2O 6.36 (structure), total 100.24 wt.%, yielding the empirical formula (K1.72Mg0.29Na0.04Ca0.01)Σ2.06(U0.98O2)(S0.98O4)2(H2O)2 based on 12 O atoms per formula unit. The Raman spectrum is dominated by the symmetric stretching vibrations of UO22+, SO42– and weaker O–H stretching vibrations. Geschieberite is orthorhombic, Pna21, with a = 13.7778(3), b = 7.2709(4), c = 11.5488(2) Å, V = 1156.92(7) Å3, Z = 4. The eight strongest powder X-ray diffraction lines are [dobs in Å (hkl) Irel]: 6.882 (200) 100, 5.622 (111) 53, 4.589 (211) 12, 4.428 (202) 16, 3.681 (311) 18, 3.403 (013) 12, 3.304 (401,1̄13) 15 and 3.006 (122) 17. The structure, refined to R = 0.028 for 1882 I > 3σ(I) reflections, contains [(UO2)(SO4)2(H2O)]2– sheets that are based on the protasite anion topology. Sheets are stacked perpendicular to a. Potassium atoms and one H2O molecule are located between these sheets, providing an interlayer linkage. The remaining H2O molecule is localized within the structural unit, at the free vertex of the uranyl pentagonal bipyramid; this vertex does not link to sulfate tetrahedra. The mineral is named for one of the most important ore veins in Jáchymov – the Geschieber vein.

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TEM/AEM characterization of fine-grained clay minerals in very-low-grade rocks: Evaluation of contamination by empa involving celadonite family minerals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165938 ◽

1996 ◽

Vol 54 ◽

pp. 694-695

Author(s):

Gejing Li ◽

D. R. Peacor ◽

D. S. Coombs ◽

Y. Kawachi

Keyword(s):

Electron Microscopy ◽

Volcanic Rocks ◽

Analytical Electron Microscopy ◽

Metamorphic Rocks ◽

New Mineral ◽

Chemical Compositions ◽

Low Grade ◽

Fine Grained ◽

Depth Analysis ◽

Mineral Aggregates

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.

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