American Mineralogist, Volume 101, pages 487–492, 2016 New Mineral Names*,† DMITRIY I. BELAKOVSKIY1 AND FERNANDO CÁMARA2 1Fersman Mineralogical Museum, Russian Academy of Sciences, Leninskiy Prospekt 18 korp. 2, Moscow 119071, Russia 2Dipartimento di Scienze della Terra, Universitá di degli Studi di Torino, Via Valperga Caluso, 35-10125 Torino, Italy IN THIS ISSUE This New Mineral Names has entries for 10 new minerals, including barikaite, deveroite-(Ce), hizenite-(Y), kobyashevite, leverettite, magnesiokoritnigite, mössbauerite, shimazakiite (4M and 4O polytypes), takanawaite-(Y), and veblenite. BARIKAITE* (650). The average of 5 electron probe WDS analyses is [wt% D. Topa, E. Makovicky, H. Tajedin, H. Putz, and G. Zagler (range)]: Ag 5.80 (4.93–5.87), Pb 35.77 (35.50–39.21), Sb 18.33 (17.49–18.37), As 15.64 (15.18–15.77), Tl 0.15(0.07–0.22), (2013) Barikaite, Pb10Ag3(Sb8As11)S19S40, a new member of the sartorite homologous series. Mineralogical Magazine, S 24.00 (23.65–23.92), total 99.69. The empirical formula on 77(7), 3039–3046. the basis of 32Me + 40S = 72 apfu is Pb9.31Ag2.90Tl0.04(Sb8.12 D. Topa and E. Makovicky (2013) The crystal structure of bari- As11.26)S19.36S40.37. The single crystal X-ray study shows barikaite kaite. Mineralogical Magazine, 77(8), 3093–3104. is monoclinic with space group P21/n and unit-cell parameters a = 8.533(1), b = 8.075(1), c = 24.828(2) Å, β = 99.077(6)°, V = 1689.2 Å3; Z = 1. The X-ray powder data was not be obtained due Barikaite (IMA 2012-055), ideally Pb10Ag3(Sb8As11)S19S40, is a new antimony-containing species of the sartorite homolo- to paucity of pure material. The strongest lines of the calculated gous series discovered at the Barika Au-Ag deposit, Azarbaijan X-ray powder diffraction pattern [d Å (I%; hkl)] are: 3.835 (63; Province of Western Iran. The lens-like deposit ~150 m long and 022), 3.646 (100; 016), 3.441 (60; 212), 3.408 (62; 214), 2.972 up to 20 m thick consists of massive banded pyrite and barite (66; 216), 2.769 (91; 222), 2.752 (78; 424), 2.133 (54; 402). ores accompanied by locally developed silica bands. Pyrite, The crystal structure of barikaite contains 8 cation sites and 10 sphalerite, galena, tetrahedrite-tennantite, and stibnite were anion sites. Four of the cation sites have mixed occupancies: the deposited during the synvolcanogenic hydrothermal activity of split sites As2-Sb2, As3-Sb3, Ag5-As5, and the site Me6 with Cretaceous age. Fractures host veinlets with Ag-As-Sb-Pb-rich three cations involved. Two sites, Pb1 and Pb2, have tricapped sulfosalts: tetrahedrite-tennantite, stephanite, pyrargyrite, trech- trigonal prismatic coordination and alternate along a. They form mannite, smithite, miargyrite, andorite, geocronite, seligmannite, zigzag walls parallel to (001). There are 3 distinct [100] columns guettardite and realgar and Ag-Au alloys. Barikaite is always of alternating cations, As1-(As,Sb)2, Sb4-(As,Sb)3, (As,Ag)5- found in association with guettardite in quartz veins hosting (Pb,Sb)6, which together form trapezoidally configured single irregular thin veinlets and nests of sulfosalts in a mass of quartz (013) layers. These layers aggregate into tightly bonded double and baryte. The mineral occurs as anhedral grains with no twin- layers, separated by lone electron pair micelles. The predomi- ning. It has been replaced by guettardite, resulting in corroded nantly As- and Sb-occupied sites are in a chess-board order. remnants of what was a solid barikaite aggregate. The mineral Barikaite is a member of the sartorite homologous series. The is grayish black, opaque, metallic with dark gray streak. It is empirical values of homolog order N derived from the chemical brittle with irregular fracture and no cleavage or parting. The analyses are in fair agreement with the crystallographic value 2 N = 4. Barikaite is a close homeotype of rathite and less closely microhardness VHN50 = 200 (192–212) kg/mm corresponds to ~3 of Mohs scale. The density could not be measured due to related to dufrénoysite (distinct, pure arsenian N = 4 members) 3 and completes the spectrum of Sb-rich members of the sartorite admixture of guettardite; Dcalc = 5.34 g/cm . In reflected light barikaite is grayish white with distinct pleochroism from white to homologous series. The mineral is named for the type locality. dark gray. Internal reflections are absent. Anisotropism is distinct The holotype specimen is deposited in the Natural History Mu- with rotation tints in shades of gray. The reflectance spectrum seum Vienna, Austria. D.B. was measured in air between 400 and 700 nm with 20 nm inter- DEVEROITE-(CE)* val. The values for COM wavelengths are [Rmin, Rmax % (nm)]: 37.0, 39.3 (470); 34.1, 36.9 (546); 33.1, 36.2 (589); 31.3, 34.1 A. Guastoni, F. Nestola, P. Gentile, F. Zorzi, M. Alvaro, A. Lanza, L. Peruzzo, M. Schiazza, and N.M. Casati (2013) Deveroite- (Ce): a new REE-oxalate from Mount Cervandone, Devero * All minerals marked with an asterisk have been approved by the IMA CNMMC. † For a complete listing of all IMA-validated unnamed minerals and their codes, Valley, Western-Central Alps, Italy. Mineralogical Magazine, see http://pubsites.uws.edu.au/ima-cnmnc/. 77(7), 3019–3026. 0003-004X/16/0002–487$05.00/DOI: http://dx.doi.org/10.2138/am-2016-NMN101216 487 488 NEW MINERAL NAMES Deveroite-(Ce) (IMA 2013-003), ideally Ce2(C2O4)3·10H2O, Neogen alkali olivine basalt closely associating with lokkaite- is a new mineral and the third natural oxalate discovered in the (Y), tengerite-(Y), and kimuraite-(Y). The mineral forms platy alpine fissures of Mount Cervandone, overlooking the Devero crystals up to 50 × 0.2 μm forming radial spherical aggregates up Valley, Piedmont, Italy. The area is characterized by swarms to 1 cm. Hizenite-(Y) is white with a white streak and vitreous to of pegmatite dikes crosscutting metamorphic rocks and hosted silky luster. The cleavage is perfect on {001}. The hardness, opti- 3 by leucocratic gneisses. These dikes containing Ba-Y-REE-As cal properties and density were not measured; Dcalc = 2.98 g/cm . minerals [aeschynite-(Y), agardite-(Y), Nb-anatase, As-fergu- The average of 5 electron probe EDS analyses [wt% (range)] is sonite-beta-(Y), cervandonite-(Ce), chernovite-(Y), crichtonite- Y2O3 27.61 (26.20–29.60), La2O3 1.11 (0.95–1.41), Pr2O3 0.65 senaite, fluorite, gadolinite-(Y), monazite-(Ce), paraniite-(Y), (0–0.89), Nd2O3 5.80 (4.69–6.72), Sm2O3 1.68 (1.04–1.97), synchysite-(Ce), and xenotime-(Y)] as well as meter-long quartz Eu2O3 0.73 (0–1.56), Gd2O3 3.82 (2.85–4.70), Tb2O3 0.24 veins crosscutting pegmatite dikes. Deveroite-(Ce) crystallization (0–0.79), Dy2O3 3.10 (2.75–3.54), Ho2O3 0.47 (0–0.93), Er2O3 related to circulation of meteoric waters enriched with oxalic 1.58 (1.02–1.83), Tm2O3 0.04 (0–0.22), Yb2O3 0.10 (0–0.51), acid. A source of oxalate is provided by incomplete oxidation CaO 5.93 (5.38–6.42), CO2 29.55 (28.78–30.32), H2O 15.03 of organic material such as decaying plant remains. A source of (14.85–15.21), total 97.44. The contents of H2O and CO2 were REE is provided by the hosting mineral, cervandonite-(Ce), and obtained by a CHN analyzer. The empirical formula based on not completely described REE-arsenosilicate. Deveroite-(Ce) oc- 47 O pfu is Ca1.76(Y4.08Nd0.58Gd0.35Dy0.28Sm0.16Er0.14La0.11Pr0.07Eu0.07 curs only on crystals of cervandonite-(Ce) and is associated with Ho0.04Tb0.02Yb0.01)Σ5.91(CO3)11.2·13.9H2O. The strongest lines of the agardite-(Ce), asbecasite, cafarsite, K-feldspar, muscovite, and X-ray powder diffraction pattern [d Å (I%; hkl)] are: 15.57 (20; quartz. It forms sprays of colorless elongated tabular or acicular 004), 10.63 (100; 006), 6.384 (77; 0.0.10), 3.962 (51; 0.0.16), prisms up to ~50 μm. It has a white streak, vitreous luster and a 3.821 (27; 029, 1.0.13), 2.060 (23; 306, 0.4.13). The orthorhom- perfect cleavage along {010}. The mineral is brittle with Mohs bic unit-cell parameters refined from the powder data are: a = hardness of ~2–2½. Density was not measured due to the size 6.295(1), b = 9.089(2), c = 63.49(1) Å, V = 3632(1) Å3, Z = 4. 3 of crystals; Dcalc = 2.352 g/cm . Fluorescence was not observed. Single-crystal X-ray diffraction study was not performed due to Deveroite-(Ce) is non-pleochroic, optically biaxial (–) with 2V the small crystal size. Unit-cell data were obtained using TEM of ~77°, and the extinction angle (Y^c) of ~27°. No twinning electron diffraction and then refined using XRD data. Hizenite- was observed. The refractive indexes were not measured but (Y) structure model suggests the alternating of Y-corrugated proposed to be very close to that of synthetic La2(C2O4)3·10H2O: sheets and Ca-H2O layers along c axes. The structure is related α = 1.473, β = 1.548, γ = 1.601°. The average of 11 electron to that of kimuraite-(Y), lokkaite-(Y), and tengerite-(Y). The probe EDS analyses [wt%, (range)] is CaO 0.34 (0.25–0.44), name is for “Hizen” the old name of the mineral type locality C2O3 (by stoichiometry) 29.7, Y2O3 1.66 (1.19–2.04), La2O3 7.29 between 7th and 16th century.
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