scholarly journals Thalhammerite, Pd9Ag2Bi2S4, a New Mineral from the Talnakh and Oktyabrsk Deposits, Noril’sk Region, Russia

Minerals ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 339 ◽  
Author(s):  
Anna Vymazalová ◽  
František Laufek ◽  
Sergey Sluzhenikin ◽  
Vladimir Kozlov ◽  
Chris Stanley ◽  
...  
Keyword(s):  
Empirical Formula ◽  
Polarized Light ◽  
Associate Professor ◽  
New Mineral ◽  
X Ray Diffraction ◽  
Average Composition ◽  
Weak Anisotropy ◽  
X Ray ◽  
Light Yellow ◽  
The University

Thalhammerite, Pd9Ag2Bi2S4, is a new sulphide discovered in galena-pyrite-chalcopyrite and millerite-bornite-chalcopyrite vein-disseminated ores from the Komsomolsky mine of the Talnakh and Oktyabrsk deposits, Noril’sk region, Russia. It forms tiny inclusions (from a few μm up to about 40–50 μm) intergrown in galena, chalcopyrite, and also in bornite. Thalhammerite is brittle and has a metallic lustre. In plane-polarized light, thalhammerite is light yellow with weak bireflectance, weak pleochroism, in shades of slightly yellowish brown and weak anisotropy; it exhibits no internal reflections. Reflectance values of thalhammerite in air (R1, R2 in %) are: 41.9/43.0 at 470 nm, 43.9/45.1 at 546 nm, 44.9/46.1 at 589 nm, and 46.3/47.5 at 650 nm. Three spot analyses of thalhammerite give an average composition: Pd 52.61, Bi 22.21, Pb 3.92, Ag 14.37, S 7.69, and Se 0.10, total 100.90 wt %, corresponding to the empirical formula Pd8.46Ag2.28(Bi1.82Pb0.32)Σ2.14(S4.10Se0.02)Σ4.12 based on 17 atoms; the average of five analyses on synthetic thalhammerite is: Pd 55.10, Bi 24.99, Ag 12.75, and S 7.46, total 100.30 wt %, corresponding to Pd8.91Ag2.03Bi2.06S4.00. The density, calculated on the basis of the empirical formula, is 9.72 g/cm3. The mineral is tetragonal, space group I4/mmm, with a 8.0266(2), c 9.1531(2) Å, V 589.70(2) Å3 and Z = 2. The crystal structure was solved and refined from the single-crystal X-ray-diffraction data of synthetic Pd9Ag2Bi2S4. Thalhammerite has no exact structural analogues known in the mineral system; chemically, it is close to coldwellite (Pd3Ag2S) and kravtsovite (PdAg2S). The strongest lines in the X-ray powder diffraction pattern of synthetic thalhammerite [d in Å (I) (hkl)] are: 3.3428(24)(211), 2.8393(46)(220), 2.5685(21)(301), 2.4122(100)(222), 2.3245(61)(123), 2.2873(48)(004), 2.2201(29)(132), 2.0072(40)(400), 1.7481(23)(332), and 1.5085(30)(404). The mineral honours Associate Professor Oskar Thalhammer of the University of Leoben, Austria.

Dalnegroite, Tl5–xPb2x(As,Sb)2l–xS34, a new thallium sulphosalt from Lengenbach quarry, Binntal, Switzerland

2009 ◽  
Vol 73 (6) ◽  
pp. 1027-1032 ◽  
Author(s):  
F. Nestola ◽  
A. Guastoni ◽  
L. Bindi ◽  
L. Secco
Keyword(s):  
Polarized Light ◽  
New Mineral ◽  
X Ray Diffraction ◽  
X Ray ◽  
Elemental Concentrations ◽  
Reflected Light ◽  
Mohs Hardness ◽  
The Mean ◽  
The University ◽  
Probable Space

AbstractDalnegroite, ideally Tl4Pb2(As12Sb8)Σ20S34, is a new mineral from Lengenbach, Binntal, Switzerland. It occurs as anhedral to subhedral grains up to 200 μm across, closely associated with realgar, pyrite, Sb-rich seligmanite in a gangue of dolomite. Dalnegroite is opaque with a submetallic lustre and shows a brownish-red streak. It is brittle; the Vickers hardness (VHN25) is 87 kg mm-2(range: 69—101) (Mohs hardness ∼3—3½). In reflected light, dalnegroite is highly bireflectant and weakly pleochroic, from white to a slightly greenish-grey. In cross-polarized light, it is highly anisotropic with bluish to green rotation tints and red internal reflections.According to chemical and X-ray diffraction data, dalnegroite appears to be isotypic with chabournéite, Tl5-xPb2x(Sb,As)21-xS34. It is triclinic, probable space groupP1, witha= 16.217(7) Å,b= 42.544(9) Å,c= 8.557(4) Å, α = 95.72(4)°, β = 90.25(4)°, γ = 96.78(4)°,V= 5832(4) Å3,Z= 4.The nine strongest powder-diffraction lines [d(Å) (I/I0) (hkl)] are: 3.927 (100) (10 0); 3.775 (45) (22); 3.685 (45) (60); 3.620 (50) (440); 3.124 (50) (2); 2.929 (60) (42); 2.850 (70) (42); 2.579 (45) (02); 2.097 (60) (024). The mean of 11 electron microprobe analyses gave elemental concentrations as follows: Pb 10.09(1) wt.%, Tl 20.36(1), Sb 23.95(1), As 21.33(8), S 26.16(8), totalling 101.95 wt.%, corresponding to Tl4.15Pb2.03(As11.86Sb8.20)S34. The new mineral is named for Alberto Dal Negro, Professor in Mineralogy and Crystallography at the University of Padova since 1976.

Viteite, Pd5InAs, a new mineral from the Monchetundra layered intrusion, Kola Peninsula, Russia

2020 ◽  
Vol 58 (3) ◽  
pp. 395-402
Author(s):  
A. Vymazalová ◽  
F. Laufek ◽  
T.L. Grokhovskaya ◽  
C.J. Stanley
Keyword(s):  
Kola Peninsula ◽  
Empirical Formula ◽  
Polarized Light ◽  
Layered Intrusion ◽  
Structure Type ◽  
New Mineral ◽  
Synthetic Analogue ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxygenated Compounds

ABSTRACT Viteite, Pd5InAs, is a new mineral discovered in the Monchetundra layered intrusion, Kola Peninsula, Russia. It forms euhedral grains about 0.5 to 10 μm in size intergrown with irarsite (IrAsS), hollingworthite (RhAsS), zvyagintsevite (Pd3Pb), Au-Ag alloys, and tulameenite (Pt2CuFe), that are replaced by Pt-Pd-Fe-Cu alloys and Pt-Pd-Fe-Cu oxygenated compounds, all of which are embedded in chalcocite, goethite, and covellite. Viteite is brittle and has a metallic luster. In plane-polarized light, viteite is bright pinkish-white. The mineral is weakly anisotropic with rotation tints blue to pinkish brown; it exhibits no internal reflections. Reflectance values of viteite in air (R1, R2 in %) are 55.7, 54.0 at 470 nm; 59.2, 58.4 at 546 nm; 60.0, 60.4 at 589 nm; and 60.0, 62.6 at 650 nm. Eight electron-microprobe analyses of viteite give an average composition of Pd 71.90, Pt 1.60, Fe 0.98, Cu 0.59, In 11.48, Hg 1.42, Pb 0.40, As 10.70, total 99.07 wt.%, corresponding to the empirical formula (Pd4.92Pt0.06)Σ4.98(In0.73Fe0.12Cu0.07Hg0.05Pb0.01)Σ0.98As1.04 based on 7 atoms; the average of 12 analyses of its synthetic analogue is: Pd 73.72, In 16.37, As 9.80, total 99.90 wt.%, corresponding to Pd5.02In1.03As0.95. The density, calculated on the basis of the empirical formula, is 10.78 g/cm3. The mineral is tetragonal, space group P4/mmm, with a 3.98600(3), c 6.98385(8) Å, V 110.961(2) Å3, and Z = 1. The crystal structure of synthetic Pd5InAs was solved and refined using powder X-ray-diffraction data from synthetic Pd5InAs. Viteite crystallizes with the Pd5TlAs structure type. The strongest lines in the X-ray powder diffraction pattern of synthetic Pd5InAs [d in Å (I) (hkl)] are: 2.3281(45)(003), 2.1932(100)(112), 1.9928(33)(020), 1.2515(17)(115), 1.1857(25)(132). The mineral is named for the Vite river, which flows near the Monchetundra intrusion.

scholarly journals Norilskite, (Pd,Ag)7Pb4, a new mineral from Noril'sk-Talnakh deposit, Russia

2017 ◽  
Vol 81 (3) ◽  
pp. 531-541 ◽  
Author(s):  
A. Vymazalová ◽  
F. Laufek ◽  
S. F. Sluzhenikin ◽  
C. J. Stanley
Keyword(s):  
Polarized Light ◽  
Structure Type ◽  
New Mineral ◽  
X Ray Diffraction ◽  
Strong Anisotropy ◽  
Average Composition ◽  
Group Mineral ◽  
X Ray ◽  
Mohs Hardness ◽  
Talnakh Deposit

AbstractNorilskite, (Pd,Ag)7Pb4 is a new platinum-group mineral discovered in the Mayak mine of the Talnakh deposit, Russia. It forms anhedral grains in aggregates (up to ∼400 μm) with polarite, zvyagintsevite, Pd-rich tetra-auricupride, Pd-Pt bearing auricupride,Ag-Au alloys, (Pb,As,Sb) bearing atokite, mayakite, Bi-Pb-rich kotulskite and sperrylite in pentlandite, cubanite and talnakhite. Norilskite is brittle, has a metallic lustre and a grey streak. Values of VHN20 fall between 296 and 342 kg mm–2, with a mean valueof 310 kg mm–2, corresponding to a Mohs hardness of ∼4. In plane-polarized light, norilskite is orange-brownish pink, has moderate to strong bireflectance, orange-pink to greyish-pink pleochroism, and strong anisotropy; it exhibits no internal reflections. Reflectancevalues of norilskite in air (Ro, Re' in %) are: 51.1, 48.8 at 470 nm, 56.8, 52.2 at 546 nm, 59.9, 53.5 at 589 nm and 64.7, 55.5 at 650 nm. Sixteen electronmicroprobe analyses of natural norilskite gave an average composition: Pd 44.33, Ag 2.68, Bi 0.33 and Pb 52.34, total99.68 wt.%, corresponding to the empirical formula (Pd6.56Ag0.39)∑6.95(Pb3.97Bi0.03)∑4.00 based on 4 Pb + Bi atoms; the average of eight analyses on synthetic norilskite is: Pd 42.95, Ag 3.87 and Pb 53.51, total 100.33wt.%, corresponding to (Pd6.25Ag0.56)∑6.81Pb4.00. The mineral is trigonal, space group P3121, with a = 8.9656(4), c = 17.2801(8) Å, V = 1202.92(9) Å3 and Z = 6. The crystalstructure was solved and refined from the powder X-ray diffraction data of synthetic (Pd,Ag)7Pb4. Norilskite crystallizes in the Ni13Ga3Ge6 structure type, related to nickeline. The strongest lines in the powder X-ray diffraction patternof synthetic norilskite [d in Å (I) (hkl)] are: 3.2201(29)(023,203), 2.3130(91)(026,206), 2.2414(100)(220), 1.6098(28)(046,406), 1.3076(38)(246,462), 1.2942(18)(600), 1.2115(37)(22.12,12.13), 0.9626(44) (06.12,60.12). The mineral is named for the locality, the Noril'sk district in Russia.

Vymazalováite, Pd3Bi2S2, a new mineral from the Noril'sk-Talnakh deposit, Krasnoyarskiy region, Russia

2018 ◽  
Vol 82 (2) ◽  
pp. 367-373 ◽  
Author(s):  
Sergei F. Sluzhenikin ◽  
Vladimir V. Kozlov ◽  
Chris J. Stanley ◽  
Maria L. Lukashova ◽  
Keith Dicks
Keyword(s):  
Empirical Formula ◽  
Electron Back Scatter Diffraction ◽  
New Mineral ◽  
X Ray Diffraction ◽  
Average Composition ◽  
Reflected Light ◽  
Structural Identity ◽  
Cell Dimensions ◽  
Average Reflectance ◽  
Talnakh Deposit

ABSTRACTVymazalováite, Pd3Bi2S2 is a new platinum-group mineral discovered in the Komsomolsky mine of the Talnakh deposit, Noril'sk district, Russia. It forms small (from a few μm to 20–35 µm) inclusions or euhedral grains in intergrowths of polarite, sobolevskite, acanthite and unnamed (Pd,Ag)5BiS2 in aggregates (up to ~200 µm) in galena and rarely in chalcopyrite. It occurs with telargpalite, cooperite, braggite, vysotskite, sopcheite, stibiopalladinite, sobolevskite, moncheite, kotulskite, malyshevite, insizwaite, Au-bearing silver and the newly described mineral kravtsovite (PdAg2S) in association with pyrite, chalcopyrite and galena in vein-disseminated mineralization in skarn rocks. Synthetic vymazalováite is brittle; it has a metallic lustre and a grey streak. In plane-polarized reflected light, vymazalováite is creamy grey and appears slightly brownish against galena in the assemblage with chalcopyrite. It exhibits no internal reflections. Average reflectance values in air for natural and synthetic vymazalováite are (R natural, R synthetic in %) are: 46.35, 45.7 at 470 nm, 47.65, 47.45 at 546 nm, 48.5, 48.2 at 589 nm and 49.5, 49.0 at 650 nm. Seven electron probe micro-analyses of vymazalováite give an average composition: Pd 40.42, Bi 49.15, Ag 0.55, Pb 1.02, S 7.77 and Se 0.26, total 99.17 wt.%, corresponding to the empirical formula Pd3.05(Bi1.89Ag0.04Pb0.04)Σ1.97(S1.95Se0.03)Σ1.98 based on a total of 7 atoms per formula unit. The simplified formula is Pd3Bi2S2. The mineral is cubic, space group I213, with a = 8.3097(9) Å, V = 573.79(1) Å3 and Z = 4. The density calculated on the basis of the empirical formula and cell dimensions of synthetic vymazalováite is 9.25 g/cm3. The strongest lines in the powder X-ray diffraction pattern of synthetic vymazalováite [d in Å (I) (hkl)] are: 4.15(32)(200), 2.93(78)(220), 2.40(100)(220), 2.08(53)(400), 1.695(34)(422), 1.468(35)(440) and 1.252(31)(622). The structural identity of natural vymazalováite with synthetic Pd3Bi2S2 was confirmed by electron back-scatter diffraction measurements on the natural sample. This new mineral honours Dr Anna Vymazalová of the Czech Geological Survey, Prague.

scholarly journals Sazhinite-(La), Na3LaSi6O15(H2O)2, a new mineral from the Aris phonolite, Namibia: Description and crystal structure

2006 ◽  
Vol 70 (4) ◽  
pp. 405-418 ◽  
Author(s):  
F. Cámara ◽  
L. Ottolini ◽  
B. Devouard ◽  
L. A. J. Garvie ◽  
F. C. Hawthorne
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Polarized Light ◽  
Total Content ◽  
New Mineral ◽  
Formula Unit ◽  
X Ray Diffraction ◽  
Average Composition ◽  
Mohs Hardness ◽  
Silicate Layers ◽  
Secondary Ion

AbstractSazhinite-(La) is a new mineral from the Aris phonolite, Windhoek, Namibia. It occurs in vesicles within the phonolite, together with other species crystallized from late-stage hydrothermal fluids: natrolite, aegirine, microcline, apophyllite, sphalerite, analcime, fluorite, villiaumite, hydroxylapatite, galena, makatite, quartz, eudialyte, kanemite, tuperssuatsiaite and korobitsynite. Sazhinite-(La) forms small euhedral crystals up to 1 mm long and 0.4 mm wide, elongated along [001] and flattened on (010), exhibiting the forms {h0l}, {100} and {001}. It has good cleavage parallel to {010} and {001}. Twinning was not observed. Crystals are brittle with a Mohs hardness of 3, creamy white with a white streak, vitreous to pearly lustre, and translucent to transparent. In plane-polarized light, crystals are colourless with a = Z, b = Y, c = X. It is biaxial positive with α = 1.524, β = 1.528, γ = 1.544, all ±0.002, 2Vz(obs) = 46(1)°, and 2Vz(calc.) = 53.6°.Sazhmite-(La) is orthorhombic Pmm2, a = 7.415(2), b = 15.515(3), c = 7.164(1) Å, and V = 824.2 Å3. One crystal was studied by X-ray diffraction, electron microprobe and secondary ion mass spectrometry (SIMS) microanalysis, leading to the average composition (Na2.87K0.02Sr0.01)Σ2.90 [La0.41Ce0.35Pr0.02Nd0.04(Sm,Gd,Dy,Er,Yb)Σ0.01Th0.09U0.01Y0.01Zr0.01Ca0.08Li0.01]Σ1.04 (S15.87S0.06B0.01) (O14.86F0.14).(H2O)2.Weighted full-matrix least-squares refinement on 3369 reflections yielded Rall = 3.8%. The structure is built of corrugated [Si6O15]6- layers linked by [7]-coordinated REE and R4+ cations. This framework leaves channels that contain three [5]- and [6]-coordinated Na cations per formula unit that compensate for the residual charge on the silicate layers. The SIMS analyses confirm a Na content of 3 atoms per formula unit, leading to an ideal formula of Na3LaSi6O15(H2O)2. The third Na atom is bonded to H2O groups and therefore the total content of both Na and H2O may be reduced to 2 and 1 per formula, respectively. The depletion in Na allows for the entrance of high-charge cations such as Th4+.

scholarly journals Gobelinite, the Co analogue of ktenasite from Cap Garonne, France, and Eisenzecher Zug, Germany

2020 ◽  
Vol 32 (6) ◽  
pp. 637-644
Author(s):  
Stuart J. Mills ◽  
Uwe Kolitsch ◽  
Georges Favreau ◽  
William D. Birch ◽  
Valérie Galea-Clolus ◽  
...  
Keyword(s):  
Empirical Formula ◽  
Old French ◽  
New Mineral ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Determinations ◽  
Jahn Teller ◽  
Mohs Hardness ◽  
Pale Green

Abstract. The new mineral gobelinite, ideally CoCu4(SO4)2(OH)6⚫6H2O, is a new member of the ktenasite group and the Co analogue of ktenasite, ZnCu4(SO4)2(OH)6⚫6H2O. It occurs at Cap Garonne (CG), Var, France (type locality), and Eisenzecher Zug (EZ), Siegerland, North Rhine-Westphalia, Germany (cotype locality). The mineral forms pale green, bluish green or greyish green, blocky to thin, lath-like crystals. They are transparent and non-fluorescent, with a vitreous, sometimes also pearly, lustre and a white streak having a pale-green cast. Mohs hardness is about 2.5. The crystals are brittle with an irregular fracture; no cleavage was observed. D(meas.) is 2.95(2) and D(calc.) is 2.907 g cm−3 (for empirical formula, CG). Common associates are brochantite and various other hydrated metal sulfates. Electron-microprobe analyses of the CG material yielded (wt. %) CuO 42.45, CoO 6.58, NiO 3.37, ZnO 3.14, SO3 22.12, and H2O 22.62 (calculated on structural grounds), and total = 100.30 wt. %, giving the empirical formula (based on 20 O atoms) (Co0.63Ni0.32Zn0.28Cu3.83)Σ5.06S1.98O20H18.00. The simplified formula is (Co,Ni)(Cu,Zn)4(SO4)2(OH)6⚫6H2O, and the endmember formula is CoCu4(SO4)2(OH)6⚫6H2O. Scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDS) analyses of the (Zn-free) EZ material gave the simplified average formula (Co0.92Ni0.21Mg0.01Cu3.79)Σ4.93(SO4)2.08(OH)6⚫6H2O. Optically, gobelinite (CG) is biaxial negative, with α=1.576(2), β=1.617(2) and γ=1.630(2); 2Vmeas=58(4)∘ and 2Vcalc=57.5∘. Dispersion is weak, r>v; orientation is X=β, Y=γ and Z≈α, with strong pleochroism X equaling colourless, Y equaling green and Z equaling pale green. The mineral is monoclinic, space group P21∕c, with a=5.599(1), b=6.084(1), c=23.676(5) Å, β=95.22(3)∘ and V=803.2(3) Å3 (at 100 K; CG) and a=5.611(1), b=6.103(1), c=23.808(5) Å, β=95.18(3)∘ and V=811.9(3) Å3 (at 298 K; EZ), respectively (Z=2). The eight strongest measured powder X-ray diffraction lines (d in Å (I) hkl (CG material)) are 11.870 (100) 002, 5.924 (40) 004, 4.883 (10) 102, 4.825 (15) 013, 3.946 (15) 006, 2.956 (15) 008, 2.663 (20) 202 and 2.561 (15) 1‾23. Single-crystal structure determinations gave R1=0.0310 (CG) and 0.0280 (EZ). The atomic arrangement is based on brucite-like sheets formed from edge-sharing, Jahn–Teller-distorted (4+2 coordination) CuO6 octahedra. These sheets are decorated on both sides with SO4 tetrahedra and linked via hydrogen bonds to interstitial, fairly regular Co(H2O)6 octahedra. The name alludes to the Old French word gobelin, equivalent to the German word kobold, from which the designation of the element cobalt was derived.

Markeyite, a new calcium uranyl carbonate mineral from the Markey mine, San Juan County, Utah, USA

2018 ◽  
Vol 82 (5) ◽  
pp. 1089-1100 ◽  
Author(s):  
Anthony R. Kampf ◽  
Jakub Plášil ◽  
Anatoly V. Kasatkin ◽  
Joe Marty ◽  
Jiří Čejka
Keyword(s):  
Secondary Phase ◽  
New Mineral ◽  
San Juan ◽  
X Ray Diffraction ◽  
X Ray ◽  
Light Yellow ◽  
Uranyl Carbonate ◽  
Laser Crystals ◽  
Mohs Hardness ◽  
San Juan County

ABSTRACTThe new mineral markeyite (IMA2016-090), Ca9(UO2)4(CO3)13·28H2O, was found in the Markey mine, San Juan County, Utah, USA, where it occurs as a secondary phase on asphaltum in association with calcite, gypsum and natrozippeite. The mineral is pale yellowish-green with white streak and fluoresces bright bluish white under a 405 nm laser. Crystals are transparent and have vitreous to pearly lustre. It is brittle, with Mohs hardness 1½ to 2, irregular fracture and three cleavages: perfect on {001}; good on {100} and {010}. The measured density is 2.68 g cm–3. Crystals are blades, flattened on {001} and elongate on [010], exhibiting the forms {100}, {010}, {001}, {110}, {101}, {011} and {111}. Markeyite is optically biaxial (–) with α = 1.538(2), β = 1.542(2) and γ = 1.545(2) (white light); the measured 2V is 81(2)°; the dispersion isr<v(weak); the optical orientation isX=c,Y=b,Z=a; and pleochroism isX= light greenish yellow,YandZ= light yellow (X>Y≈Z). Electron microprobe analyses (energy-dispersive spectroscopy mode) yielded CaO 18.60, UO342.90, CO221.30 (calc.) and H2O 18.78 (calc.), total 101.58 wt.% and the empirical formula Ca8.91(U1.01O2)4(CO3)13·28H2O. The six strongest powder X-ray diffraction lines are [dobsÅ(I)(hkl)]: 10.12(69)(001), 6.41(91)(220,121), 5.43(100)(221), 5.07(33)(301,002,131), 4.104(37)(401,141) and 3.984(34)(222). Markeyite is orthorhombic,Pmmn,a= 17.9688(13),b= 18.4705(6),c= 10.1136(4) Å,V= 3356.6(3) Å3andZ= 2. The structure of markeyite (R1= 0.0435 for 3427Fo> 4σF) contains uranyl tricarbonate clusters (UTC) that are linked by Ca–O polyhedra forming thick corrugated heteropolyhedral layers. Included within the layers is an additional disordered CO3group linking the Ca–O polyhedra. The layers are linked to one another and to interlayer H2O groups only via hydrogen bonds. The structure bears some similarities to that of liebigite.

Shannonite, Pb2OCO3, a new mineral from the Grand Reef Mine, Graham County, Arizona, USA

1995 ◽  
Vol 59 (395) ◽  
pp. 305-310 ◽  
Author(s):  
A. C. Roberts ◽  
J. A. R. Stirling ◽  
G. J. C. Carpenter ◽  
A. J. Criddle ◽  
G. C. Jones ◽  
...  
Keyword(s):  
Empirical Formula ◽  
Short Wave ◽  
New Mineral ◽  
Orthorhombic Space Group ◽  
Weak Anisotropy ◽  
Calculated Density ◽  
X Ray ◽  
Cell Parameters ◽  
New Mineral Species ◽  
Transmission Electron

AbstractShannonite, ideally Pb2OCO3, is a new mineral species that occurs as mm-sized white porcellanous crusts, associated with fluorite, at the Grand Reef mine, Graham County, Arizona, USA. Other associated minerals are plumbojarosite, hematite, Mn-oxides, muscovite-2M1, quartz, litharge, massicot, hydrocerussite, minium, and unnamed PbCO3·2PbO. Shannonite is orthorhombic, space group P21221 or P212121, with unit-cell parameters (refined from X-ray powder data): a 9.294(3), b 9.000(3), c 5.133(2) Å, V 429.3(3) Å3, a:b:c 1.0327:1:0.5703, Z = 4. The strongest five lines in the X-ray powder pattern [d in Å (I)(hkl)] are: 4.02(40)(111); 3.215(100)(211); 3.181(90)(121); 2.858(40)(130); 2.564(35)(002). The average of eight electron microprobe analyses is PbO 89.9(5), CO2 (by CHN elemental analyser) 9.70, total 99.60 wt.%. With O = 4, the empirical formula is Pb1.91C1.05O4.00. The calculated density for the empirical formula is 7.31 and for the idealized formula is 7.59 g/cm3. In reflected light, shannonite is colourless-grey to white, with ubiquitous white internal reflections (× 16 objectives), weak anisotropy, barely detectable bireflectance, and no evidence of pleochroism. The calculated refractive index (at 590 nm) is 2.09. Measured reflectance values in air and in oil (× 4 objectives) are tabulated. Transmission electron-microscopy studies reveal that individual crystallites range in size from 10–400 nm, are platy, and are anhedral. Physical properties for cryptocrystalline crusts include: white streak; waxy lustre; opaque; nonfluorescent under both long- and short-wave ultraviolet light; uneven fracture; brittle; VHN100 97 (range 93–100); calculated Mohs’ hardness 3–3½. Shannonite is soluble in concentrated HCl and in dilute HNO3 and H2SO4. The mineral name is for David M. Shannon, who helped collect the samples and who initiated this study.

scholarly journals Omariniite, Cu8Fe2ZnGe2S12, the germanium analogue of stannoidite, a new mineral species from Capillitas, Argentina

2017 ◽  
Vol 81 (5) ◽  
pp. 1151-1159 ◽  
Author(s):  
Luca Bindi ◽  
Hubert Putz ◽  
Werner H. Paar ◽  
Christopher J. Stanley
Keyword(s):  
Polarized Light ◽  
New Mineral ◽  
Polished Section ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
New Mineral Species ◽  
Catamarca Province ◽  
Brownish Black ◽  
The University

AbstractOmariniite, ideally Cu8Fe2ZnGe2S12, represents the Ge-analogue of stannoidite and was found in bornite-chalcocite-rich ores near the La Rosario vein of the Capillitas epithermal deposit, Catamarca Province, Argentina. The mineral is associated closely with three other Ge-bearing minerals (putzite, catamarcaite, rarely zincobriartite) and bornite, chalcocite, digenite, covellite, sphalerite, tennantite, luzonite, wittichenite, thalcusite and traces of mawsonite. The width of the seams rarely exceeds 60 μm, their length can attain several 100 μm. The mineral is opaque, orange-brown in polished section, has a metallic lustre and a brownish-black streak. It is brittle, and the fracture is irregular to subconchoidal. Neither cleavage nor parting are observable in the sections. In plane-polarized light omariniite is brownish-orange and has a weak pleochroism. Internal reflections are absent. The mineral is distinctly anisotropic with rotation tints varying between brownish-orange and greenish-brown. The average result of 45 electron-microprobe analyses is Cu 42.18(34), Fe 9.37(26), Zn 5.17(43), In 0.20(6), Ge 11.62(22), S 31.80(20), total 100.34(46) wt.%. The empirical formula, based on Σ(Me + S) = 25, is Cu8.04(Fe2.03In0.02)Σ2.05Zn0.96 Ge1.94S12.01, ideally Cu8+Fe2+Zn2+Ge24+S122-. Omariniite is orthorhombic, space group I222, with unit-cell parameters: a = 10.774(1), b = 5.3921(5), c = 16.085(2) Å, V = 934.5(2) Å3, a:b:c = 1.9981:1:2.9831, Z = 2. X-ray single-crystal studies (R1 = 0.023) revealed the structure to be a sphalerite derivative identical to that of stannoidite. Omariniite is named after Dr. Ricardo Héctor Omarini (1946–2015), Professor at the University of Salta, for his numerous contributions to the geology of Argentina.

Kurilite – Ag8Te3Se – a new mineral from the Prasolovskoe deposit, Kuril islands, Russian Federation

2010 ◽  
Vol 74 (3) ◽  
pp. 463-468 ◽  
Author(s):  
V. A. Kovalenker ◽  
O. Yu. Plotinskaya ◽  
C. J. Stanley ◽  
A. C. Roberts ◽  
A. M. McDonald ◽  
...  
Keyword(s):  
Russian Federation ◽  
Empirical Formula ◽  
Polarized Light ◽  
New Mineral ◽  
Unit Cell Parameters ◽  
Calculated Density ◽  
X Ray ◽  
Cell Parameters ◽  
Kunashir Island ◽  
Mohs Hardness

AbstractKurilite, with the simplified formula, Ag8Te3Se, is a new mineral from the Prasolovskoe epithermal Au-Ag deposit, Kunashir Island, Kuril arc, Russian Federation. It occurs as aggregates up to 2 mm in size, composed of brittle xenomorphic grains, up to several μm in size, in quartz, associated with tetrahedrite, hessite, sylvanite and petzite. Kurilite is opaque, grey, with a metallic lustre and a black streak. Under plane-polarized light, kurilite is white with no observed bireflectance, cleavage, or parting observed. Under crossed polars it appears isotropic without internal reflections. Reflectance values in air and in oil, are tabulated. It has a mean VHN (25 g load) of 99.9 kg/mm2 which equates roughly to a Mohs hardness of 3. Electron microprobe analyses yield a mean composition of Ag 63.71, Au 0.29, Te 29.48, Se 5.04, S 0.07, total 98.71 wt.%. The empirical formula (based on 12 atoms) is (Ag7.97Au0.02)Σ7.99Te3.00(Se0.86Te0.12S0.03)Σ1.01. The calculated density is 7.799 g/cm3 (based on the empirical formula and unit-cell parameters refined from single-crystal data). Kurilite is rhombohedral, R3 or , a 15.80(1), c 19.57(6) Å, V 4231(12)Å3, c:a 1.2386, Z = 15. Its crystal structure remains unsolved. The seven strongest lines of the X-ray powder-diffraction pattern [d in Å (I)(hkl)] are: 3.727(20)(131), 2.996(50)(232), 2.510(30)(226,422), 2.201(100)(128,416,342), 2.152(20)(603), 2.079(30)(253), 2.046(20)(336,434). The mineral is named after the locality.

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