scholarly journals Natropalermoite, Na2SrAl4(PO4)4(OH)4, a new mineral isostructural with palermoite, from the Palermo No. 1 mine, Groton, New Hampshire, USA

2017 ◽  
Vol 81 (4) ◽  
pp. 833-840 ◽  
Author(s):  
Benjamin N. Schumer ◽  
Hexiong Yang ◽  
Robert T. Downs
Keyword(s):  
New Hampshire ◽  
Powder Diffraction ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Cell Parameter ◽  
New Mineral ◽  
Orthorhombic Space Group ◽  
Calculated Density ◽  
X Ray ◽  
Mohs Hardness

AbstractNatropalermoite, ideally Na2SrAl4(PO4)4(OH)4, the Na-analogue of palermoite, is a new mineral from the Palermo No. 1 mine, Groton, New Hampshire, USA. Associated minerals are palermoite, eosphorite and quartz. Natropalermoite crystal sare prismatic with striations parallel to the direction of elongation (the a axis) up to 200 μm × 50 μm × 45 μm in size. The mineral is colourless, transparent with a white streak and vitreous lustre and is visually indistinguishable from palermoite. It is brittle with subconchoidal fracture and has a Mohs hardness of 5.5. Cleavage is perfect on {001}, fair on {100} and no parting was observed. The calculated density is 3.502 g cm–3. Natropalermoite is biaxial (–), α = 1.624(1), β = 1.641(1), γ = 1.643(1) (589nm), 2Vmeas = 43(4)°, 2Vcalc = 38°. An electron microprobe analysis yielded an empirical formula (based on 20 O apfu) of (Na1.69Li0.31)∑2.00(Sr0.95Mg0.04Ca0.02Ba0.01)∑1.02(Al3.82Mn0.03Fe0.03)∑3.88(P1.01O4)4(OH)4.Natropalermoite is orthorhombic, space group Imcb, a = 11.4849(6), b = 16.2490(7), c = 7.2927(4) Å, V = 1360.95(17) Å3, Z = 4. Natropalermoite is isotypic with palermoite, but substitution of the larger Na for Li results in substantial increase of the b cell parameter. Four of the seven Na–O distances are longer than their equivalents in palermoite, resulting in a more regular 7-fold coordination polyhedron about Na. The eight strongest peaks in the calculated X-ray powder diffraction are [dcalc(Å),Irel%, (hkl)]: [3.128, 100, (321)], [4.907, 68, (121)], [3.327, 48, (022)], [4.689, 45, (220)], [3.078, 45, (202)], [2.453, 38, (242)], [2.636, 35, (411)], [2.174, 35, (422)].

Wooldridgeite, Na2(P2O7)2(H2O)10: A new mineral from Judkins Quarry, Warwickshire, England

1999 ◽  
Vol 63 (1) ◽  
pp. 13-16 ◽  
Author(s):  
F. C. Hawthorne ◽  
M. A. Cooper ◽  
D. I. Green ◽  
R. E. Starkey ◽  
A. C. Roberts ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Infrared Absorption Spectrum ◽  
Short Wave ◽  
New Mineral ◽  
Calculated Density ◽  
X Ray ◽  
Mohs Hardness ◽  
Unit Formula

AbstractWooldridgeite, ideally Na2(P2O7)2(H2O)10, orthorhombic, a = 11.938(1), b = 32.854(2), c = 11.017(1) Å , V = 4321.2(8) Å3, a:b:c = 0.3634:1:0.3353, space group Fdd2, Z = 8, is a new mineral from Judkins Quarry, Nuneaton, Warwickshire, England. Associated minerals are calcite, chalcopyrite, bornite and baryte. It occurs as equant crystals forming rhombic dipyramids; no twinning was observed. It is transparent blue-green with a very pale-blue streak, a vitreous lustre, and does not fluoresce under long- or short-wave ultraviolet light. Wooldridgeite has a Mohs hardness of 2–3, is brittle with an irregular fracture, and has no cleavage. The calculated density is 2.279 g/cm3. In transmitted light, wooldridgeite is colourless, non-pleochroic, and shows no dispersion. It is biaxial negative with α = 1.508(1), β = 1.511(1), γ = 1.517(1), 2V(meas.) = 76.2(5), 2V(calc.) = 71(10)8, X = b, Y = c, Z = a. The strongest five reflections in the X-ray powder diffraction pattern are [d(Å), (I), (hkl)]: 8.23(30)(040), 6.52(100)(131), 4.05(40)(260), 3.255(40)(262); 2.924(40)(371). Electron-microprobe analysis of wooldridgeite gave P2O5 39.37, CuO 20.24, MgO 0.24, CaO 7.73, Na2O 8.33, K2O 0.17, H2O(calc.) 24.72, sum 100.80 wt.%; the corresponding unit formula (based on 24 anions) is (Na1.96K0.03)Ca1.00(Cu1.85Mg0.04)P4.04O14(H2O)10 where the H2O groups were assigned from knowledge of the crystal structure; the infrared absorption spectrum also indicates the presence of H2O in the structure. The mineral is named for James Wooldridge (1923–1995), a fervent amateur mineral collector who discovered this mineral.

Belakovskiite, Na7(UO2)(SO4)4(SO3OH)(H2O)3, a new uranyl sulfate mineral from the Blue Lizard mine, San Juan County, Utah, USA

2014 ◽  
Vol 78 (3) ◽  
pp. 639-649 ◽  
Author(s):  
A. R. Kampf ◽  
J. Plášil ◽  
A. V. Kasatkin ◽  
J. Marty
Keyword(s):  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
New Mineral ◽  
San Juan ◽  
Uranyl Sulfate ◽  
Calculated Density ◽  
Secondary Alteration ◽  
X Ray ◽  
Mohs Hardness ◽  
San Juan County

AbstractThe new mineral belakovskiite (IMA2013-075), Na7(UO2)(SO4)4(SO3OH)(H2O)3, was found in the Blue Lizard mine, Red Canyon, White Canyon district, San Juan County, Utah, USA, where it occurs as a secondary alteration phase in association with blödite, ferrinatrite, kröhnkite, meisserite and metavoltine. Crystals of belakovskiite are very pale yellowish-green hair-like fibres up to 2 mm long and usually no more than a few mm in diameter. The fibres are elongated on [100] and slightly flattened on {021}. Crystals are transparent with a vitreous lustre. The mineral has a white streak and a probable Mohs hardness of ∼2. Fibres are flexible and elastic, with brittle failure and irregular fracture. No cleavage was observed. The mineral is readily soluble in cold H2O. The calculated density is 2.953 g cm−3. Optically, belakovskiite is biaxial (+) with α = 1.500(1), β = 1.511(1) and γ = 1.523(1) (measured in white light). The measured 2V is 87.1(6)° and the calculated 2V is 88°. The mineral is non-pleochroic. The partially determined optical orientation is X ≈ a. Electron-microprobe analysis provided Na2O 21.67, UO3 30.48, SO3 40.86, H2O 6.45 (structure), total 99.46 wt.% yielding the empirical formula Na6.83(U1.04O2)(SO4)4(S0.99O3OH)(H2O)3 based on 25 O a.p.f.u. Belakovskiite is triclinic, P, with a = 5.4581(3), b = 11.3288(6), c = 18.4163(13) Å, α = 104.786(7)°, β = 90.092(6)°, γ = 96.767(7)°, V = 1092.76(11) Å3 and Z = 2. The eight strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 8.96(35)(002), 8.46(29)(011), 5.19(100)(01,101,10), 4.66(58)(013,02,0,110), 3.568(37)(120,023,005,03), 3.057(59)(06,15,31), 2.930(27)(multiple) and 1.8320(29)(multiple). The structure, refined to R1 = 5.39% for 3163 Fo > 4σF reflections, contains [(UO2)(SO4)4(H2O)]6− polyhedral clusters connected via an extensive network of Na−O bonds and H bonds involving eight Na sites, three other H2O sites and an SO3OH (hydrosulfate) group. The 3-D framework, thus defined, is unique among known uranyl sulfate structures. The mineral is named for Dmitry Ilych Belakovskiy, a prominent Russian mineralogist and Curator of the Fersman Mineralogical Museum.

Hydroniumpharmacosiderite, a new member of the pharmacosiderite supergroup from Cornwall, UK: structure and description

2010 ◽  
Vol 74 (5) ◽  
pp. 863-869 ◽  
Author(s):  
S. J. Mills ◽  
A. R. Kampf ◽  
P. A. Williams ◽  
P. Leverett ◽  
G. Poirier ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Diffraction Pattern ◽  
Powder Diffraction ◽  
Empirical Formula ◽  
Direct Methods ◽  
Structure Type ◽  
New Mineral ◽  
Calculated Density ◽  
X Ray ◽  
Mohs Hardness

AbstractHydroniumpharmacosiderite, ideally (H3O)Fe4(AsO4)3(OH)4·4H2O, is a new mineral from Cornwall, UK, probably from the St. Day group of mines. It occurs as a single yellowish green, slightly elongated cube, measuring 0.17 mm ×0.14 mm ×0.14 mm. The mineral is transparent with a vitreous lustre. It is brittle with a cleavage on {001}, has an irregular fracture, a white streak and a Mohs hardness of 2–3 (determined on H3O-exchanged pharmacosiderite). Hydroniumpharmacosiderite has a calculated density of 2.559 g cm–3 for the empirical formula. The empirical formula, based upon 20.5 oxygen atoms, is: [(H3O)0.50K0.48Na0.06]1.04(Fe3.79Al0.22)4.01[(As2.73P0.15)2.88O12](OH)4·4H2.14O. The five strongest lines in the X-ray powder diffraction pattern are [dobs(Å),Iobs,(hkl)]: 8.050,100,(001); 3.265,35,(112); 2.412,30,(113); 2.830,23,(202); 4.628,22,(111). Hydroniumpharmacosiderite is cubic, space group with a = 7.9587(2) Å, V = 504.11(2) Å3 and Z = 1. The crystal structure was solved by direct methods and refined to R1 = 0.0481 for 520 reflections with I > 2σ(I). The structure is consistent with determinations for H3O-exhchanged pharmacosiderite and the general pharmacosiderite structure type.

Northstarite, a new lead-tellurite-thiosulfate mineral from the North Star mine, Tintic, Utah, USA

2020 ◽  
Vol 58 (4) ◽  
pp. 533-542
Author(s):  
Anthony R. Kampf ◽  
Robert M. Housley ◽  
George R. Rossman
Keyword(s):  
Raman Spectrum ◽  
Powder Diffraction ◽  
Electron Microprobe ◽  
Empirical Formula ◽  
New Mineral ◽  
Calculated Density ◽  
Space Group ◽  
X Ray ◽  
The North ◽  
Mohs Hardness

ABSTRACT Northstarite, Pb6(Te4+O3)5(S2O3), is a new mineral from the North Star mine, Tintic district, Juab County, Utah, USA. It is an oxidation-zone mineral occuring in a vug in massive quartz-baryte-enargite-pyrite in association with anglesite, azurite, chrysocolla, fluorapatite, plumbogummite, tellurite, zincospiroffite, and the new mineral adanite. Crystals are beige short prisms with pyramidal terminations, up to about 1 mm in length. The mineral is transparent to translucent with adamantine luster, white streak, Mohs hardness 2, brittle tenacity, irregular fracture, and no cleavage. The calculated density is 6.888 g/cm3. Northstarite is uniaxial (–) and nonpleochroic. The Raman spectrum is consistent with the presence of tellurite and thiosulfate groups and the absence of OH and H2O. Electron-microprobe analyses gave the empirical formula Pb5.80Sb3+0.05Te4+5.04S6+1.02S2–1.02O18. The mineral is hexagonal, space group P63, with a = 10.2495(5), c = 11.6677(8) Å, V = 1061.50(13) Å3, and Z = 2. The five strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 3.098(100)(113), 2.957(88)(300), 2.140(42)(223), 1.7335(41)(413), and 1.6256(31)(306). The structure (R1 = 0.033 for 1476 I > 2σI reflections) is a framework constructed of short (strong) Pb–O and Te–O bonds with channels along the 63 axes. The thiosulfate groups at the centers of the channels are only weakly bonded to the framework.

Canutite, NaMn3[AsO4][AsO3(OH)]2, a new protonated alluaudite-group mineral from the Torrecillas mine, Iquique Province, Chile

2014 ◽  
Vol 78 (4) ◽  
pp. 787-795 ◽  
Author(s):  
A. R. Kampf ◽  
S. J. Mills ◽  
F. Hatert ◽  
B. P. Nash ◽  
M. Dini ◽  
...  
Keyword(s):  
Powder Diffraction ◽  
White Light ◽  
Electron Microprobe ◽  
New Mineral ◽  
Optical Orientation ◽  
Calculated Density ◽  
Secondary Alteration ◽  
Group Mineral ◽  
X Ray ◽  
Mohs Hardness

AbstractThe new mineral canutite (IMA2013-070), NaMn3[AsO4][AsO3(OH)]2, was found at two different locations at the Torrecillas mine, Salar Grande, Iquique Province, Chile, where it occurs as a secondary alteration phase in association with anhydrite, halite, lavendulan, magnesiokoritnigite, pyrite, quartz and scorodite. Canutite is reddish brown in colour. It forms as prisms elongated on [20] and exhibiting the forms {010}, {100}, {10}, {201} and {102}, or as tablets flattened on {102} and exhibiting the forms {102} and {110}. Crystals are transparent with a vitreous lustre. The mineral has a pale tan streak, Mohs hardness of 2½, brittle tenacity, splintery fracture and two perfect cleavages, on {010} and {101}. The calculated density is 4.112 g cm−3. Optically, canutite is biaxial (+) with α = 1.712(3), β = 1.725(3) and γ = 1.756(3) (measured in white light). The measured 2V is 65.6(4)°, the dispersion is r < v (slight), the optical orientation is Z = b; X ^ a = 18° in obtuse β and pleochroism is imperceptible. The mineral is slowly soluble in cold, dilute HCl. The empirical formula (for tabular crystals from near the mineshaft), determined from electron - microprobe analyses, is (Na1.05Mn2.64Mg0.34Cu0.14Co0.03)∑4.20As3O12H1.62. Canutite is monoclinic, C2/c, a = 12.3282(4), b = 12.6039(5), c = 6.8814(5) Å, β = 113.480(8)°, V = 980.72(10) Å3 and Z = 4. The eight strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 6.33(34)(020), 4.12(26)(21), 3.608(29)(310,31), 3.296(57)(12), 3.150(28)(002,131), 2.819(42)(400,041,330), 2.740(100)(240,02,112) and 1.5364(31)(multiple). The structure, refined to R1 = 2.33% for 1089 Fo > 4σF reflections, shows canutite to be isostructural with protonated members of the alluaudite group.

Gatehouseite, a new manganese hydroxy phosphate from Iron Monarch, South Australia

1993 ◽  
Vol 57 (387) ◽  
pp. 309-313 ◽  
Author(s):  
A. Pring ◽  
W. D. Birch
Keyword(s):  
Empirical Formula ◽  
Microprobe Analysis ◽  
South Australia ◽  
New Mineral ◽  
Calculated Density ◽  
X Ray ◽  
Pale Yellow ◽  
Orthorhombic Cell ◽  
Mohs Hardness ◽  
Hematite Ore

AbstractGatehouseite is a new manganese hydroxy phosphate from Iron Monarch, South Australia. The new mineral occurs as radiating clusters of pale yellow, and yellow to pale brownish orange bladed crystals up to 100 ~tm in length. The crystals are elongated along [010] and the principal forms are {102}, {110} and {001}. Gatehouseite also occurs as overgrowths on prismatic arsenoclasite crystals. Associated with gatehouseite are baryte, shigaite, manganoan ferroan calcite, hausmannite and hematite. Gatehouseite appears to have formed at low temperature by the interaction of phosphorus-rich fluids on hausmannite in carbonate-rich fractures in the hematite ore. Electron microprobe analysis yielded: MnO 64.42, FeO 0.19, CuO 0.03, ZnO 0.03, PbO 0.05, Al2O3 0.10, P2O5 22.18, V2O5 0.38, As2O5 3.58, H2O (6.44%). These data gave an empirical formula of Mn5.09Fe0.01Al0.01(P1.75As0.17-V0.02)∑1.94O8(OH)4.00, calculated on the basis of 12 oxygen atoms. The simplified formula is Mn5(PO4)2(OH)4. The mineral is transparent with a pale yellow streak, an adamantine lustre and an estimated Mohs hardness of 4. The crystals exhibit a distinct cleavage on {010} and have a splintery fracture. The strongest lines in the X-ray powder pattern are (dobs, Iobs, hkl) 4.48 (10) (004); 4.03 (10) (104); 2.900 (100) (11.5); 2.853 (70) (106); 2.801 (50) (021); 2.702 (80) (303); 2.022 (15) (322); 1.608(15) (330). These data were indexed on an orthorhombic cell, with a = 9.097(2), b = 5.693(2), c = 18.002(10) Å and a volume of 932.4(8) Å3; the space group is probably P212121. For Z = 4 and using the empirical formula, the calculated density is 3.74 g/cm3. Optical properties could not be determined in full; two refractive indices are 1.74(1) and 1.76(1) (white light); pleochroism is distinct from brown to near colourless. The crystals are length slow with parallel extinction. The name is for Dr. Bryan Michael Kenneth Cummings Gatehouse (1932-), crystal chemist of Monash University, Melbourne, Australia.

Chenite, Pb4Cu(SO4)2(OH)6, a new mineral, from Leadhills, Scotland

1986 ◽  
Vol 50 (355) ◽  
pp. 129-135 ◽  
Author(s):  
W. H. Paar ◽  
Kurt Mereiter ◽  
R. S. W. Braithwaite ◽  
Paul Keller ◽  
P. J. Dunn
Keyword(s):  
Powder Diffraction ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Refractive Indices ◽  
New Mineral ◽  
Secondary Mineral ◽  
X Ray ◽  
Infra Red ◽  
The Ideal

AbstractChenite, a new lead-copper secondary mineral, has been found on specimens from the Leadhills area, Scotland. It is associated with caledonite, linarite, leadhillite, susannite, and other species, on oxidized galena with chalcopyrite. Electron microprobe analysis yielded PbO 74.5, CuO 7.8, SO3 13.3, H2O 4.4 (by difference), sum = 100 wt. %. The empirical formula (based on 14 oxygens) is Pb3.98Cu1.17S1.98O14H5.82; the ideal formula is Pb4Cu(SO4)2(OH)6, which requires PbO 75.2, CuO 6.7, SO3 13.5, H2O 4.6, sum = 100 wt. %.Infra-red spectroscopy showed the presence of only and OH− ions, with no H2O.Chenite is triclinic, P1 or P̄, with a = 5.791(1), b = 7.940(1), c = 7.976(1) Å, α = 112.02(1), β = 97.73(1), γ = 100.45(1)°, V = 326.0 Å3, Z = 1. The strongest lines in the X-ray powder diffraction pattern (d, I/Io, hkl) are: 5.55, 7, 100; 4.32, 6, 11; 3.60, 10 002; 3.41, 9, 10; 3.30, 5, 02; 3.00, 5, 111; 2.80, 7, 12; 2.07, 6, 211/21/13; 1.778, 5, 3/23.Chenite forms minute, singly terminated, transparent to translucent sky-blue crystals from 0.1 to over 1 mm long, elongated approximately [032]. Twenty different forms (pinacoids) have been identified on the four crystals studied. A good cleavage on {100}, and traces of a second on {001}, can be observed. Optically, chenite is biaxial negative, 2 V(measured) = 67±1°, 2 V(calc.) = 68° (Na). The refractive indices are α 1.871±0.005, β 1.909±0.005, γ 1.927±0.005 (Na). Dispersion is strong, r≫v. The mineral is weakly pleochroic. H (Mohs) ∼ 2½. D = 5.98, and calculated Dx = 6.044 g cm−3.

Fassinaite, Pb22+(S2O3)(CO3), the first mineral with coexisting thiosulphate and carbonate groups:d escription and crystal structure

2011 ◽  
Vol 75 (6) ◽  
pp. 2721-2732 ◽  
Author(s):  
L. Bindi ◽  
F. Nestola ◽  
U. Kolitsch ◽  
A. Guastoni ◽  
F. Zorzi
Keyword(s):  
Empirical Formula ◽  
Optical Data ◽  
New Mineral ◽  
Orthorhombic Space Group ◽  
Calculated Density ◽  
X Ray ◽  
Cell Parameters ◽  
Mohs Hardness ◽  
Ray Density ◽  
Oxygen Atoms

AbstractFassinaite, ideally Pb22+(S2O3)(CO3), is a new mineral from the Trentini mine, Mount Naro, Vicenza Province, Veneto, Italy (holotype locality). It is also reported from the Erasmus adit, Schwarzleo District, Leogang, Salzburg, Austria and the Friedrich-Christian mine, Schapbach, Black Forest, Baden-Wurttemberg, Germany (cotype localities). At the Italian type locality it occurs as acicular [010]. colourless crystals up to 200 μn long, closely associated with galena, quartz and anglesite. At the Austrian cotype locality it is associated with cerussite, rare sulphur and very rare phosgenite. At the German cotype locality anglesite is the only associated phase. Fassinaite crystals commonly have flat chisel-shaped terminations. They are transparent with vitreous to adamantine lustre and a white streak. Fassinaite is brittle with an irregular fracture and no discernible cleavage; the estimated Mohs hardness is 11/2—2. The calculated density for the type material is 6.084 g cm–3 (on the basis of the empirical formula), whereas the X-ray density is 5.947 g cm–3. In common with other natural lead thiosulphates (i.e. sidpietersite and steverustite) fassinaite has intense internal reflections, which do not allow satisfactory optical data to be collected; the crystals are length-slow and have very high birefringence. The mineral is not fluorescent.Fassinaite is orthorhombic, space group Pnma, with unit-cell parameters (for the holotype material) a = 16.320(2), b = 8.7616(6), c = 4.5809(7) Å, V = 655.0(1) Å3, a:b:c = 1.863:1:0.523, Z = 4. Single-crystal structural studies were carried out on crystals from all three localities: R1(F) values range between 0.0353 and 0.0596. The structure consists of rod-like arrangements of Pb-centred polyhedra that extend along the [010] direction. These ‘rods’ are linked, alternately, by (CO3)2– and (S2O3)2– groups. The (S2O3)2– groups point alternately left and right (in a projection on [001] with [010] set vertical) if the apex occupied by the S2– in the thiosulphate group is defined to be the atom giving the direction. The lead atoms are nine-coordinated by seven oxygen atoms and two sulphur (S2–) atoms. The eight strongest X-ray powder-diffraction lines [d in Å (I/I0) (hkl)] are: 4.410 (39) (101), 4.381 (59) (020), 4.080 (62) (400), 3.504 (75) (301), 3.108 (100) (121), 2.986 (82) (420), 2.952 (49) (221) and 2.736 (60) (321). Electron-microprobe analyses produce an empirical formula Pb2.01(1)(S1.82(2)O3)CO3 (on the basis of six oxygen atoms). The presence of both carbonate and thiosulphate groups was corroborated by Raman spectra, which are discussed in detail. Fassinaite is named after Bruno Fassina (b. 1943), an Italian mineral collector who discovered the mineral in 2009.

Fluorapophyllite-(NH4), NH4Ca4(Si8O20)F⋅8H2O, a new member of the apophyllite group from the Vechec quarry, eastern Slovakia

2020 ◽  
Vol 84 (4) ◽  
pp. 533-539
Author(s):  
Martin Števko ◽  
Jiří Sejkora ◽  
Jakub Plášil ◽  
Zdeněk Dolníček ◽  
Radek Škoda
Keyword(s):  
Crystal Structure ◽  
Brittle Fracture ◽  
Powder Diffraction ◽  
Slovak Republic ◽  
The Other ◽  
New Mineral ◽  
Calculated Density ◽  
X Ray ◽  
Perfect Cleavage ◽  
Mohs Hardness

AbstractThe new mineral fluorapophyllite-(NH4), ideally NH4Ca4(Si8O20)F⋅8H2O, was found at the Vechec andesite quarry located near Vechec village, Vranov nad Topľou Co., Prešov Region, Slovak Republic. It occurs in cavities of quartz–illite–saponite–tobelite xenolith embedded in pyroxene andesite. Fluorapophyllite-(NH4) is associated with calcite, tridymite, pyrite, chabazite-Ca and heulandite-Ca. It forms clusters, aggregates or crystalline crusts consisting of individual, well-developed crystals up to 4 mm in size, exhibiting the forms {110}, {101} and {001}. The mineral is colourless to light pink and translucent with white streak and vitreous to pearly lustre; it is non-fluorescent under ultraviolet radiation. The Mohs hardness is ~4½ to 5, tenacity is brittle, fracture is irregular, and there is perfect cleavage on {001}. The calculated density is 2.325 g cm–3. Fluorapophyllite-(NH4) is optically uniaxial (+) with ω = 1.5414(5) and ɛ = 1.5393(8) (λ = 589 nm). It is non-pleochroic. The empirical formula (based on 29 O + F apfu) is [(NH4)0.55K0.32Na0.07Ca0.06]Σ1.00(Ca4.01Mg0.02)Σ4.03Si7.97O20[F0.84(OH)0.16]Σ1.00⋅8H2O. Fluorapophyllite-(NH4) is tetragonal, space group P4/mnc, a = 8.99336(9) Å, c = 15.7910(3) Å, V = 1277.18(3) Å3 and Z = 2. The seven strongest X-ray powder diffraction lines are [dobs in Å,(I,%)(hkl)]: 7.897(32)(002), 7.812(13)(101), 4.547(14)(103), 3.946(100)(004), 2.985(39)(105), 2.4841(11)(215) and 1.5788(12)(00.10). The crystal structure of fluorapophyllite-(NH4), refined to R1 = 0.0299 for 743 unique (I > 3σI) observed reflections, confirmed that the atomic arrangement is very similar to that of the other members of the apophyllite group. The new mineral is named according to the current nomenclature scheme for apophyllite-group minerals and is an NH4 dominant analogue of fluorapophyllite-(K), fluorapophyllite-(Na) and fluorapophyllite-(Cs).

scholarly journals Retzian-(La), a new mineral from Sterling Hill, Sussex County, New Jersey

1984 ◽  
Vol 48 (349) ◽  
pp. 533-535 ◽  
Author(s):  
Pete J. Dunn ◽  
Donald R. Peacor ◽  
William B. Simmons
Keyword(s):  
Rare Earth ◽  
New Jersey ◽  
Diffraction Pattern ◽  
Powder Diffraction ◽  
Microprobe Analysis ◽  
New Mineral ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Sussex County ◽  
Dominant Member

AbstractRetzian-(La), ideally, Mn2La(AsO4)(OH)4, is a new rare-earth analogue of retzian and retzian-(Nd). It was found associated with willemite, calcite, and franklinite, in the Stealing Hill Mine, Ogdensburg, Sussex County, New Jersey, USA. Retzian-(La) is orthorhombic, space group Pban, with a = 5.670(7), b = 12.01(1), and c = 4.869(8) Å. The strongest lines in the X-ray powder diffraction pattern are (d,I/I0,hkl): 3.51 80 111, 2.715 100 131, 1.848 50 061, 1.456 40. Microprobe analysis yielded MnO 25.2, MgO 3.7, ZnO 1.2, As2O5 26.5, La2O3 10.6, Ce2O3 8.8, Nd2O3 8.2, Pr2O3 5.1, Sm2O3 2.2, Y2O3 2.5, H2O [7.7], sum = 101.7 wt. %, corresponding to an La-dominant member of the retzian series.Retzian-(La) forms 0.5 mm euhedral crystals composed of the forms {001}, {010}, {110}, and {150}; the crystals have pseudohexagonal habit. It is reddish-brown, with vitreous luster, no cleavage, density > 4.2 g/cm3. Optically, it is biaxial, positive, 2V = 82° with α = 1.766, β = 1.773, and γ = 1.788. Dispersion is strong, r > v; pleochroism is very weak; orientation is X = c, Y= b, Z = a; absorption is Z > Y > X.

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