naa a22 4500 510736270 CHVBK 20180411083011.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1134/S1075701513070088 doi (NATIONALLICENCE)springer-10.1134/S1075701513070088 Steklite, KAl(SO4)2: A finding at the Tolbachik Volcano, Kamchatka, Russia, validating its status as a mineral species and crystal structure [Elektronische Daten] [M. Murashko, I. Pekov, S. Krivovichev, A. Chernyatyeva, V. Yapaskurt, A. Zadov, M. Zelensky] Steklite KAl(SO4)2 has been found in sublimates of the Yadovitaya (Poisonous) fumarole at the second cinder cone of the northern breach of the Great Fissure Tolbachik Eruption, Tolbachik volcano, Kamchatka Peninsula, Russia. Steklite was approved as a valid mineral species by the Commission on New Minerals, Nomenclature, and Mineral Classification of the International Mineralogical Association on June 2, 2011 (IMA no. 2011-041). The name steklite is left for this mineral, as it was named by Chesnokov et al. (1995) for its technogenic analog from a burnt dump of coal mine no. 47 at Kopeisk, the Southern Urals, Russia. It is named after the Russian word steklo, meaning glass, in allusion to the visual similarity of its lamellae to thin glass platelets. At Tolbachik, steklite is associated with alumoklyuchevskite, langbeinite, euchlorine, fedotovite, chalcocyanite, hematite, and lyonsite. It occurs as hexagonal or irregular-shaped lamellar crystals with the major form {001} reaching 30 μm in thickness and 0.2 mm (occasionally up to 1 mm) in width. The crystals are frequently split. They are combined into openwork aggregates or thin crusts up to 1.5 × 2.5 cm in area. Steklite is transparent and colorless, with vitreous luster. The cleavage is perfect, parallel to (001). The mineral is brittle. The Mohs' hardness is 2.5. D calc is 2.797 g/cm3. Steklite is optically uniaxial, (−), ω = 1.546(2), ɛ = 1.533(3). The chemical composition (wt %, electron-microprobe data) is as follows: 0.09 Na2O, 18.12 K2O, 0.08 CaO, 0.03 MnO, 2.02 Fe2O3, 18.18 Al2O3, 61.80 SO3. The total is 100.37. The empirical formula calculated on the basis of eight O atoms is: (K0.997Na0.008Ca0.004)Σ1.009(Al0.925Fe 0.066 3+ Mg0.003Mn0.001)Σ0.995S2.01O8. Steklite is trigonal, space group P321, a = 4.7281(3), c = 7.9936(5) Å, V = 154.76(17)Å3, Z =1. The strongest reflections in the X-ray powder diffraction pattern (d, Å-I[hkl]) are: 8.02-34[001], 4.085-11[100], 3.649-100[011, 101], 2.861-51[012, 102], 2.660 - 19[003], 2.364-25[110], 2.267-14[111, 111, 103], 1.822-12[022, 202]. In the structure of steklite examined in microtwinned crystal with R = 0.0732, the SO4 tetrahedral anions are shared-corners with distorted AlO6 trigonal prisms to form ∞ 2 [(Al, Fe) (SO4)2]− layers coplanar to (001). The K+ cations are in the interlayer space. The type specimen of steklite is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow. Pleiades Publishing, Ltd., 2013 Murashko M. ZAO Systematic Mineralogy, 11 liniya 44, 199178, St. Petersburg, Russia aut Pekov I. Faculty of Geology, Moscow State University, 119991, Moscow, Russia aut Krivovichev S. St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut Chernyatyeva A. St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut Yapaskurt V. Faculty of Geology, Moscow State University, 119991, Moscow, Russia aut Zadov A. NPP Teplokhim OOO, Dmitrovskoe sh. 71, Building 2, 127238, Moscow, Russia aut Zelensky M. Institute of Experimental Mineralogy, Russian Academy of Sciences, 142432, Chernogolovka, Moscow oblast, Russia aut Geology of Ore Deposits Springer US; http://www.springer-ny.com 55/7(2013-12-01), 594-600 1075-7015 55:7<594 2013 55 11477 https://doi.org/10.1134/S1075701513070088 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1134/S1075701513070088 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Murashko M. ZAO Systematic Mineralogy, 11 liniya 44, 199178, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Pekov I. Faculty of Geology, Moscow State University, 119991, Moscow, Russia aut NATIONALLICENCE 700 1- Krivovichev S. St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Chernyatyeva A. St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Yapaskurt V. Faculty of Geology, Moscow State University, 119991, Moscow, Russia aut NATIONALLICENCE 700 1- Zadov A. NPP Teplokhim OOO, Dmitrovskoe sh. 71, Building 2, 127238, Moscow, Russia aut NATIONALLICENCE 700 1- Zelensky M. Institute of Experimental Mineralogy, Russian Academy of Sciences, 142432, Chernogolovka, Moscow oblast, Russia aut NATIONALLICENCE 773 0- Geology of Ore Deposits Springer US; http://www.springer-ny.com 55/7(2013-12-01), 594-600 1075-7015 55:7<594 2013 55 11477 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer