naa a22 4500 510736297 CHVBK 20180411083011.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1134/S1075701513070052 doi (NATIONALLICENCE)springer-10.1134/S1075701513070052 Hillesheimite, (K,Ca,□)2(Mg,Fe,Ca,□)2[(Si,Al)13O23(OH)6](OH) · 8H2O, a new phyllosilicate mineral of the Günterblassite group [Elektronische Daten] [N. Chukanov, N. Zubkova, I. Pekov, D. Belakovskiy, W. Schüller, B. Ternes, G. Blass, D. Pushcharovsky] A new mineral, hillesheimite, has been found in the Graulai basaltic quarry, near the town of Hillesheim, the Eifel Mountains, Rhineland-Palatinate (Rheinland-Pfalz), Germany. It occurs in the late assemblage comprising nepheline, augite, fluorapatite, magnetite, perovskite, priderite, götzenite, lamprophyllite-group minerals, and åkermanite. Colorless flattened crystals of hillesheimite reaching 0.2 × 1 × 1.5 mm in size and aggregates of the crystals occur in miarolitic cavities in alkali basalt. The mineral is brittle, with Mohs' hard-ness 4. Cleavage is perfect parallel to (010) and distinct on (100) and (001). D calc = 2.174 g/cm3, D meas = 2.16(1) g/cm3. IR spectrum is given. Hillesheimite is biaxial (−), α = 1.496(2), β = 1.498(2), γ = 1.499(2), 2V meas = 80°. The chemical composition (electron microprobe, mean of 4 point analyses, H2O determined from structural data, wt %) is as follows: 0.24 Na2O, 4.15 K2O, 2.14 MgO, 2.90 CaO, 2.20 BaO, 2.41 FeO, 15.54 Al2O3, 52.94 SiO2, 19.14 H2O, total is 101.65. The empirical formula is: K0.96Na0.08Ba0.16Ca0.56Mg0.58Fe 0.37 2+ [Si9.62Al3.32O23(OH)6][(OH)0.82(H2O)0.18] · 8H2O. The crystal structure has been determined from X-ray single-crystal diffraction data, R = 0.1735. Hillesheimite is orthorhombic, space group Pmmn, the unit-cell dimensions are: a = 6.979(11), b = 37.1815(18), c = 6.5296(15) Å; V=1694(3) Å3, Z = 2. The crystal structure is based on the block [(Si,Al)13O25(OH)4] consisting of three single tetrahedral layers linked via common vertices and is topologically identical to the triple layers in günterblassite and umbrianite. The strong reflections [d Å (I %)] in the X-ray powder diffraction pattern are: 6.857(58), 6.545(100), 6.284(53), 4.787(96), 4.499(59), 3.065(86), 2.958(62), 2.767(62). The mineral was named after its type locality. Type specimens are deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, registration number 4174/1. Pleiades Publishing, Ltd., 2013 Chukanov N. Institute of Problems of Chemical Physics, Russian Academy of Sciences, 142432, Chernogolovka, Moscow oblast, Russia aut Zubkova N. Faculty of Geology, Moscow State University, 119234, Moscow, Russia aut Pekov I. Faculty of Geology, Moscow State University, 119234, Moscow, Russia aut Belakovskiy D. Fersman Mineralogical Museum, Russian Academy of Sciences, Leninsky pr. 8-2, 117071, Moscow, Russia aut Schüller W. Straussenpesch 22, 53518, Adenau, Germany aut Ternes B. Bahnhofstrasse 45, 56727, Mayen, Germany aut Blass G. Merzbachstrasse 6, D-52249, Eschweiler, Germany aut Pushcharovsky D. Faculty of Geology, Moscow State University, 119234, Moscow, Russia aut Geology of Ore Deposits Springer US; http://www.springer-ny.com 55/7(2013-12-01), 549-557 1075-7015 55:7<549 2013 55 11477 https://doi.org/10.1134/S1075701513070052 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1134/S1075701513070052 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chukanov N. Institute of Problems of Chemical Physics, Russian Academy of Sciences, 142432, Chernogolovka, Moscow oblast, Russia aut NATIONALLICENCE 700 1- Zubkova N. Faculty of Geology, Moscow State University, 119234, Moscow, Russia aut NATIONALLICENCE 700 1- Pekov I. Faculty of Geology, Moscow State University, 119234, Moscow, Russia aut NATIONALLICENCE 700 1- Belakovskiy D. Fersman Mineralogical Museum, Russian Academy of Sciences, Leninsky pr. 8-2, 117071, Moscow, Russia aut NATIONALLICENCE 700 1- Schüller W. Straussenpesch 22, 53518, Adenau, Germany aut NATIONALLICENCE 700 1- Ternes B. Bahnhofstrasse 45, 56727, Mayen, Germany aut NATIONALLICENCE 700 1- Blass G. Merzbachstrasse 6, D-52249, Eschweiler, Germany aut NATIONALLICENCE 700 1- Pushcharovsky D. Faculty of Geology, Moscow State University, 119234, Moscow, Russia aut NATIONALLICENCE 773 0- Geology of Ore Deposits Springer US; http://www.springer-ny.com 55/7(2013-12-01), 549-557 1075-7015 55:7<549 2013 55 11477 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer