50 research outputs found
Patynite, NaKCa4[Si9O23], a New Mineral from the Patynskiy Massif, Southern Siberia, Russia
The new mineral patynite was discovered at the massif of Patyn Mt. (Patynskiy massif), Tashtagolskiy District, Kemerovo (Kemerovskaya) Oblast\u2019, Southern Siberia, Russia. Patynite forms lamellae up to 1 0.5 cm and is closely intergrown with charoite, tokkoite, diopside, and graphite. Other associated minerals include monticellite, wollastonite, pectolite, calcite, and orthoclase. Patynite is colorless in individual lamellae to white and white-brownish in aggregates. It has vitreous to silky luster, white streaks, brittle tenacity, and stepped fractures. Its density measured by flotation in Clerici solution is 2.70(2) g/cm3; density calculated from the empirical formula is 2.793 g/cm3. The Mohs\u2019 hardness is 6. Optically, patynite is biaxial (\u2013) with \u3b1 = 1.568(2), \u3b2 = 1.580(2), and \u3b3 = 1.582(2) (589 nm). The 2V (measured) = 40(10) and 2V (calculated) = 44.1. The Raman and IR spectra shows the absence in the mineral of H2O, OH\u2013, and CO32\u2013 groups and B\u2013O bonds. The chemical composition is (electron microprobe, wt.%): Na2O 3.68, K2O 5.62, CaO 26.82, SiO2 64.27, total 100.39. The empirical formula based on 23 O apfu is Na1.00K1.00Ca4.02Si8.99O23. Patynite is triclinic, space group P\u20131. The unit-cell parameters are: a = 7.27430(10), b = 10.5516(2), c = 13.9851(3) \uc5, \u3b1 = 104.203(2)\ub0, \u3b2 = 104.302(2)\ub0, \u3b3 = 92.0280(10)\ub0, V = 1003.07(3) \uc53, Z = 2. The crystal structure was solved by direct methods and refined to R1 = 0.032. Patynite is an inosilicate with a new type of sextuple branched tubular chain [(Si9O23)10\u2013] with an internal channel and [(Si18O46)20\u2013] as the repeat unit. The strongest lines of the powder X-ray diffraction pattern [dobs, \uc5 (I, %) (hkl)] are: 3.454 (100) (2-1-1), 3.262 (66) (2-1-2), 3.103 (64) (02-4), 2.801 (21), 1.820 (28) (40-2). Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia with the registration number 5369/1
Eudialyte-group minerals from the Monte de Trigo alkaline suite, Brazil: composition and petrological implications
Ion Exchange Properties of Günterblassite and Gmelinite, Prototypes of Microporous Materials for Water Purification
Balliranoite, (Na,K)6Ca2(Si6Al6O24)Cl2(CO3), a new cancrinite-group mineral from Monte Somma - Vesuvio volcanic complex, Italy
The new cancrinite-group mineral balliranoite was found in a metasomatic rock from Monte Somma – Vesuvio volcanic
complex, Campania, Italy. Associated minerals are orthoclase, phlogopite, clinohumite, calcite, diopside, pargasite, hau¨yne and
apatite. The mineral is named for the Italian crystallographer Paolo Ballirano. Balliranoite is transparent, colourless. It occurs in the
cavities of the rock as coarse prismatic crystals up to 1 1 2mmand as anhedral grains up to 1 cmin the groundmass. The mineral
is brittle, with Mohs hardness 5 and perfect cleavage on (10-10). Dmeas is 2.48(1), Dcalc is 2.486(12) g/cm3. Optically, the new mineral
is uniaxial (þ), o ¼ 1.523(2), e ¼ 1.525(2). IR spectrum is given. The chemical composition is (mean of 5 analyses, wt%):
Na2O 13.05, K2O 3.08, CaO 12.70, Al2O3 27.28, SiO2 32.38, SO3 1.96, Cl 7.43, –O¼Cl2 1.68; CO2 (determined by
selective sorption of ignition products) 3.24; H2O (determined by Penfield method) 0.19; total 99.63. The empirical formula
based on 12 (Si þ Al) is: Na4.70Ca2.53K0.73(Si6.02Al5.98O23.995)Cl2.34(CO3)0.82(SO4)0.270.12H2O. The simplified formula is:
Na5KCa2(Si6Al6O24)Cl2(CO3). The crystal structure was refined (R ¼ 0.0396). Balliranoite is hexagonal, P63; a ¼ 12.695(2) A ˚ ,
c ¼ 5.325(1) A ˚ , V ¼ 743.2(2) A ˚ 3, Z ¼ 1. Balliranoite is an analogue of cancrinite with . . .–Ca–Cl–Ca–Cl–. . . chains in narrow
channels instead of . . .–Na–H2O–Na–H2O–. . . and an analogue of davyne with prevailing of (CO3) in the broad channels instead of
(SO4). The strongest lines of the powder diffraction pattern [d, A˚ (I, %) (hkl)] are: 4.797 (100) (101), 3.669 (57) (300), 3.281 (73)
(211), 2.754 (16) (400), 2.662 (58) (002), 2.446 (31) (401), 2.120 (18) (330). The holotype specimen is deposited in Fersman
Mineralogical Museum of Russian Academy of Sciences, Moscow, Russia, with the registration number 3756/1
Långbanshyttanite, a new low-temperature arsenate mineral with a novel structure from Långban, Sweden
New Data on Fiedlerite-1A from Ancient Slags of Lavrion, Greece: Crystal Structure and Hydrogen Bonding
Abstract: The crystal structure (R = 0.0750) of fiedlerite-1A Pb3Cl4F (OH) · H2O from ancient slags of Lavrion (Greece) was studied on a single crystal. The mineral is triclinic, a = 8.5741 (7) Å, b = 8.0480 (5) Å, c = 7.2695 (4) Å, α = 90.087 (5), β = 102.126 (6), γ = 103.424 (6)°, V = 476.37 (6) Å3, Z = 2. The Pb2+ cations center the Pb(1)F(H2O)Cl6, Pb(2)(OH)2FCl5, and Pb(3)(OH)F2Cl5 bicapped trigonal prisms. In the structure there is an additional position Pb', filled by 10% with Pb2+. There are two main structural fragments alternating along the a axis: (100) layers of Pb(2)- and Pb(3)-centred polyhedra and zigzag chains, stretched along the b axis formed by Pb(1)-centred polyhedra sharing common edges. The IR spectrum of fiederlite-1A is given. © 2019, Pleiades Publishing, Ltd
The crystal structure of the compound Pb6Cu+(AsO3)2Cl7 discovered in the ancient slags of Lavrion, Greece
Lead and copper(I) chloride arsenite was found in the ancient metallurgic slag from the Vrissaki area, Lavrion district, Attikí Peninsula, Greece. Its chemical composition corresponds to the idealized formula Pb6Cu+(AsO3)2Cl7. The IR spectrum shows the presence of AsO33- anions and only a trace amount of O-H bonds. The crystal structure was solved by direct methods and refined to R(F) = 0.0304 based on 1778 unique reflections with I > 2s(I). The compound is trigonal (rhombohedral), R3, a = 9.8691(2), c = 34.2028(13) Å, V = 2885.01(14) Å3, Z = 6. Two crystallographically nonequivalent As3+ cations occupy apexes of the AsO3 pyramids. Cu+ cation occupies an apex of the CuCl3 pyramid. The group [Cl3Cu-AsO3] is arranged along the c axis. Pb cations occupy two sites with seven- and eight-fold coordination. The crystalchemical formula of the compound is Pb6(Cu+Cl3)(As3+O3)2Cl4